U.S. patent application number 16/045097 was filed with the patent office on 2019-01-31 for anodizable aluminum alloy plate and method of manufacturing the same.
This patent application is currently assigned to Samsung Electronics Co., Ltd. The applicant listed for this patent is Samsung Electronics Co., Ltd. Invention is credited to Go-Eun KIM, Kyung-Tae KIM, Min-Hyouk KIM, Yu-Geun KIM, Ki-Seok KWON, Joon-Ki YUN.
Application Number | 20190032237 16/045097 |
Document ID | / |
Family ID | 65138146 |
Filed Date | 2019-01-31 |
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United States Patent
Application |
20190032237 |
Kind Code |
A1 |
KIM; Go-Eun ; et
al. |
January 31, 2019 |
ANODIZABLE ALUMINUM ALLOY PLATE AND METHOD OF MANUFACTURING THE
SAME
Abstract
An anodizable aluminum plate and a method of manufacturing the
anodizable aluminum plate are provided. An aluminum alloy material
is provided, and the aluminum alloy material is anodized at a
temperature at a voltage in a range of 4 volts (V) to 14 V.
Inventors: |
KIM; Go-Eun;
(Gyeongsangbuk-do, KR) ; KWON; Ki-Seok;
(Gyeongsangbuk-do, KR) ; KIM; Kyung-Tae;
(Gyeongsangbuk-do, KR) ; KIM; Min-Hyouk;
(Gyeonggi-do, KR) ; KIM; Yu-Geun; (Gyeonggi-do,
KR) ; YUN; Joon-Ki; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd, |
Gyeonggi-do |
|
KR |
|
|
Assignee: |
Samsung Electronics Co.,
Ltd,
|
Family ID: |
65138146 |
Appl. No.: |
16/045097 |
Filed: |
July 25, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04M 1/0283 20130101;
C25D 11/246 20130101; C25D 11/04 20130101; C22C 21/02 20130101;
C25D 11/22 20130101; C25D 13/12 20130101; C25D 11/243 20130101;
C22C 21/08 20130101; C25D 11/16 20130101 |
International
Class: |
C25D 11/16 20060101
C25D011/16; C25D 11/22 20060101 C25D011/22; C25D 11/24 20060101
C25D011/24 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 25, 2017 |
KR |
10-2017-0094094 |
Claims
1. A method of manufacturing an anodizable aluminum plate, the
method comprising: providing an aluminum alloy material; and
anodizing the aluminum alloy material at a voltage in a range of 4
volts (V) to 14 V.
2. The method of claim 1, wherein anodizing the aluminum alloy
material comprises anodizing the alloy material at a temperature in
a range of 5.degree. C. to 30.degree. C. and at voltage in a range
of 4 V to 10 V for 5 to 180 minutes.
3. The method of claim 2, wherein anodizing the aluminum alloy
material comprises a pretreatment process, an anodizing process, a
sealing process, and an elution process.
4. The method of claim 3, wherein anodizing the aluminum alloy
material further comprises a coloring process.
5. The method of claim 3, further comprising: polishing the
aluminum alloy material or forming surface unevenness after
providing the aluminum alloy material.
6. The method of claim 5, wherein polishing the aluminum alloy
material comprises a physical polishing process of wet or dry
polishing of a surface of the aluminum alloy material, and wherein
a 60-degree gloss meter value of the anodizable aluminum plate on
which the physical polishing process has been performed is 100 to
800 GU.
7. The method of claim 5, wherein polishing the aluminum alloy
material comprises an electrolytic polishing process in which the
aluminum alloy material is polished at a temperature ranging from a
room temperature to 90.degree. C. and a voltage in a range of 10 V
to 50 V.
8. The method of claim 7, wherein the 60-degree gloss meter value
of the anodizable aluminum plate on which the electrolytic
polishing process has been performed is 200 to 500 gloss units
(GU).
9. The method of claim 2, wherein: the anodized aluminum plate
includes a plurality of pores, and a length of a cross-section of a
structure including at least one pore and walls surrounding the
pore is in a range of 0.30 micrometers (.mu.m) to 0.55 .mu.m, and
the 60-degree gloss meter value of the anodized aluminum plate is
200 GU or more.
10. The method of claim 2, wherein the anodized aluminum plate has
a color difference meter value of brightness (L) of 85.00 or
more.
11. The method of claim 10, wherein the anodized aluminum plate has
the color difference meter value of hue (a) of -0.40 or more and
the color difference meter value of saturation (b) of 3.00 or
less.
12. The method of claim 2, further comprising: protecting an
anodized surface by performing coating on a surface of the anodized
aluminum plate after the anodizing of the aluminum alloy
material.
13. The method of claim 12, wherein protecting the anodized surface
comprises at least one of electrophoretic coating, a process of
coating a high-hardness thin film including an organic and/or
inorganic hybrid resin, and a deposition process using a metal and
an inert gas.
14. An anodizable aluminum plate, wherein the anodizable aluminum
plate has a 60-degree gloss meter value of at least 120 gloss units
(GU) through an anodizing treatment using a voltage in a range of 4
volts (V) to 10 V.
15. The anodizable aluminum plate of claim 14, wherein the anodized
aluminum plate includes a plurality of pores, and a length of a
cross section of a structure including at least one pore and a wall
surrounding the pore is in a range of 0.30 micrometers (.mu.m) to
0.55 .mu.m.
16. The anodizable aluminum plate of claim 14, wherein the
anodizable aluminum plate includes a white color, which has a color
difference meter value of brightness (L) of 85.00 or more.
17. The anodizable aluminum plate of claim 16, wherein the
anodizable aluminum plate includes the white color which has a
numerical color difference meter value of hue (a) of -0.40 or more
and a color difference meter value of saturation (b) of 3.00 or
less.
18. The anodizable aluminum plate of claim 14, wherein the
anodizable aluminum plate comprises an aluminum 6xxx series alloy,
which contains 0.2-1.0 wt % of silicon (Si), 0.4-1.2 wt % of
magnesium (Mg), and a remainder includes aluminum (Al) and at least
one impurity.
19. The anodizable aluminum plate of claim 18, wherein the at least
one impurity of the aluminum 6xxx series alloy is at least one of
iron (Fe), copper (Cu), manganese (Mn), chromium (Cr), zinc (Zn),
and titanium (Ti).
20. An electronic device including an exterior material made of an
aluminum alloy, the electronic device comprising: a housing
comprising a front cover facing a first direction and a rear cover
facing a second direction opposite the first direction, and
including a transparent region, which forms at least a portion of
the front cover; and a display device disposed in the housing and
having a screen region exposed through the front cover, wherein the
housing includes an aluminum 6xxx series alloy, and has a 60-degree
gloss meter value of at least 120 gloss units (GU) through an
anodizing treatment using a voltage in a range of 4 volts (V) to 10
V.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35
U.S.C. .sctn. 119(a) to Korean Patent Application Serial No.
10-2017-0094094, which was filed in the Korean Intellectual
Property Office on Jul. 25, 2017, the content of which is
incorporated herein by reference.
BACKGROUND
1. Field
[0002] The present disclosure relates generally to the use of
aluminum in exterior surfaces of electronic devices, and more
particularly, to an anodizable aluminum plate and a method of
manufacturing the same.
2. Description of the Related Art
[0003] Due to the development of information communication
technology and semiconductor technology, the distribution and use
of various electronic devices has rapidly increased. Electronic
devices may perform specific functions according to programs
incorporated therein.
[0004] Aluminum has been widely used as an exterior material for
high-quality portable electronic devices. An aluminum alloy
material is mainly composed of aluminum, and major alloying
elements thereof include copper, magnesium, manganese, silicon,
tin, zinc, etc.
[0005] In order to use the aluminum alloy material as an exterior
material, various surface treatment methods are used. The surface
treatment methods include an anodizing method in which an anode is
electrically energized and a metal surface is oxidized by oxygen
generated by the anode, so that an aluminum oxide film can be
produced on the metal surface. When the anodizing treatment is
performed on the aluminum alloy material, grains having a diameter
of several nanometers in an oxide film (Al.sub.2O.sub.3) uniformly
grow to several tens of micrometers, and the hardness of the
produced oxide film is high, so that the abrasion resistance of
aluminum can be improved. The surface of the anodized metal has a
metal-specific texture, thereby providing a high aesthetic
property. Further, an anodized metal has a corrosion-resistant
surface, so that the anodized metal is excellent in corrosion
resistance.
[0006] As the enlargement, thickness reduction, and portability of
electronic devices have become more important, aluminum alloys
having high strength are used. A design demand for a ceramic
texture is also increasing. However, ceramics are poor in
moldability, workability, and rigidity as an exterior material when
compared with aluminum alloys. Anodized aluminum alloys implement a
metallic texture, but cannot provide a soft-looking appearance that
is provided by a ceramic surface.
[0007] In addition, conventional anodized aluminum alloys cannot
implement a white color preferred by many consumers, and since the
metal texture is not uniformly exhibited, it is difficult to apply
the aluminum alloys as an exterior material for electronic
devices.
SUMMARY
[0008] The present disclosure has been made to address at least the
above problems and/or disadvantages and to provide at least the
advantages described below. Accordingly, an aspect of the present
disclosure provides an aluminum alloy plate, and a method of
manufacturing the same, with a surface having a ceramic texture,
which is highly demanded in design, in addition to a metal texture
by anodizing an aluminum alloy according to predetermined
conditions.
[0009] Another aspect of the present disclosure provides an
aluminum plate, and a method of manufacturing the same, with a
high-gloss white color plate without an additional coloring
process.
[0010] An additional aspect of the present disclosure provides an
aluminum plate, and a method of manufacturing the same, with
various colors having a high-gloss ceramic texture.
[0011] A further aspect of the present disclosure provide an
aluminum plate, and a method for manufacturing the same, having
improved strength and being excellent in surface characteristics
and mechanical characteristics through an anodizing treatment.
[0012] According to an embodiment, a method is provided for
manufacturing an anodizable aluminum plate in which an aluminum
alloy material is provided, and the aluminum alloy material is
anodized at a temperature at a voltage in a range of 4 V to 14
V.
[0013] According to another embodiment, an anodizable aluminum
plate is provided that includes an aluminum 6xxx series alloy and
having a 60-degree gloss meter value of at least 120 gloss units
(GU) through an anodizing treatment using a voltage in a range of 4
V to 10 V.
[0014] According to a further embodiment, an electronic device is
provided that includes an exterior material made of an aluminum
alloy. The electronic device includes a housing having a front
cover facing a first direction and a rear cover facing a second
direction opposite the first direction, and including a transparent
region, which forms at least a portion of the front cover, and a
display device disposed in the housing and including a screen
region exposed through the front cover. The housing includes an
aluminum 6xxx series alloy having a 60-degree gloss meter value of
at least 120 GU through an anodizing treatment using a voltage in a
range of 4 V to 10 V.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above and other aspects, features, and advantages of the
present disclosure will be more apparent from the following
detailed description when taken in conjunction with the
accompanying drawings, in which:
[0016] FIG. 1 is a flowchart illustrating a method for
manufacturing a plate using an aluminum alloy, according to an
embodiment;
[0017] FIG. 2 is a graph illustrating a gloss unit measured using
an anodizing 60-degree gloss meter for various values of voltage,
using an aluminum 6xxx series alloy, according to an
embodiment;
[0018] FIGS. 3A to 3C are graphs illustrating color difference
meter values obtained using an aluminum 6xxx series alloy after
anodizing aluminum 6xxx series alloy at various voltage values,
according to an embodiment;
[0019] FIG. 4A is a diagram illustrating an enlarged schematic view
of a portion of the internal structure of an aluminum plate, which
has been subjected to a conventional anodizing treatment;
[0020] FIG. 4B is a diagram illustrating an enlarged schematic view
of a portion of the inner structure of an aluminum plate 200, which
has been subjected to an anodizing treatment, according to an
embodiment;
[0021] FIG. 5A is a diagram illustrating a schematic enlarged
perspective view of a portion (for a unit area S1) of the aluminum
plate of FIG. 4A, which has been subjected to a conventional
anodizing treatment;
[0022] FIG. 5B is a diagram illustrating a schematic enlarged
perspective view of a portion (for a unit area S2) of the aluminum
plate of FIG. 4B, which has been subjected to an anodizing
treatment, according to an embodiment;
[0023] FIG. 6A is a diagram illustrating a cross-sectional view
taken along line A-A' of an aluminum plate, which has been
subjected to a conventional anodizing treatment (excluding a
coloring process) of FIG. 5A;
[0024] FIG. 6B is a diagram illustrating a cross-sectional view of
the aluminum plate 300 taken along the line B-B' in FIG. 5B, which
has been subjected to an anodizing treatment (excluding a coloring
process), according to an embodiment;
[0025] FIG. 7A is a diagram illustrating a cross-sectional view
taken along line A-A' of an aluminum plate 30, which has been
subjected to a conventional anodizing treatment (including a
coloring process) of FIG. 5A;
[0026] FIG. 7B is a diagram illustrating a cross-sectional view of
the aluminum plate 300 taken along the line B-B' in FIG. 5B, which
has been subjected to an anodizing treatment (including a coloring
process), according to an embodiment;
[0027] FIG. 8A is an image obtained through scanning electron
microscopy (SEM) analysis by capturing an anodized film obtained by
applying a voltage of 14V and then performing a Focused Ion Beam
(FIB) treatment of the anodized film, according to an
embodiment;,
[0028] FIG. 8B is an image obtained through SEM analysis by
capturing an anodized film obtained by applying a voltage of 8V and
then performing a FIB treatment of the anodized film, according to
an embodiment; and
[0029] FIG. 9 is a diagram illustrating an exploded perspective
view illustrating an electronic device that includes a display
device configured with an aluminum alloy, according to an
embodiment.
DETAILED DESCRIPTION
[0030] Embodiments of the present disclosure are described in
detail with reference to the accompanying drawings. The same or
similar components may be designated by the same or similar
reference numerals although they are illustrated in different
drawings. Detailed descriptions of constructions or processes known
in the art may be omitted to avoid obscuring the subject matter of
the present disclosure.
[0031] As used herein, the expressions "have", "may have",
"include", and "may include" refer to the existence of a
corresponding feature (e.g., numeral, function, operation, or
constituent element such as component), and do not exclude one or
more additional features.
[0032] Herein, the expressions "A or B", "at least one of A and B",
and "one or more of A and B" may include all possible combinations
of the items listed. For example, the expressions "A or B", "at
least one of A and B", and "at least one of A and B" refer to all
of: (1) including at least one A; (2) including at least one B; and
(3) including all of at least one A and at least one B.
[0033] The expressions "a first", "a second", "the first", and "the
second", as used herein, may modify various components regardless
of the order and/or the importance, but do not limit the
corresponding components. For example, a first user device and a
second user device indicate different user devices although both
are user devices. For example, a first element may be referred to
as a second element, and similarly, a second element may be
referred to as a first element without departing from the scope of
the present disclosure.
[0034] It should be understood that when an element (e.g., first
element) is referred to as being (operatively or communicatively)
"connected," or "coupled," to another element (e.g., second
element), it may be directly connected or coupled to the other
element or any other element (e.g., third element) may be
interposed between them. In contrast, it may be understood that
when an element (e.g., first element) is referred to as being
"directly connected," or "directly coupled" to another element
(second element), there are no elements (e.g., third element)
interposed between them.
[0035] The expression "configured to", as used herein, may be used
interchangeably with, for example, "suitable for", "having the
capacity to", "designed to", "adapted to", "made to", or "capable
of", according to the situation. The term "configured to" may not
necessarily imply "specifically designed to" in hardware.
Alternatively, in some situations, the expression "device
configured to" may mean that the device, together with other
devices or components, "is able to". For example, the phrase
"processor adapted (or configured) to perform A, B, and C" may mean
a dedicated processor (e.g., embedded processor) only for
performing the corresponding operations or a generic-purpose
processor (e.g., central processing unit (CPU) or application
processor (AP)) that can perform the corresponding operations by
executing one or more software programs stored in a memory
device.
[0036] The terms used herein are merely for the purpose of
describing particular embodiments and are not intended to limit the
scope of other embodiments. A singular expression may include a
plural expression unless they are definitely different in context.
Unless defined otherwise, all terms used herein, including
technical and scientific terms, have the same meanings as those
commonly understood by a person skilled in the art to which the
present disclosure pertains. Such terms as those defined in a
generally used dictionary may be interpreted to have the same
meanings as the contextual meanings in the relevant field of art,
and are not to be interpreted to have ideal or excessively formal
meanings unless clearly defined in the present disclosure. In some
cases, even terms defined in the present disclosure should not be
interpreted to exclude embodiments.
[0037] An electronic device, according to various embodiments, may
include at least one of, for example, a smart phone, a tablet PC, a
mobile phone, a video phone, an electronic book reader (e-book
reader), a desktop PC, a laptop PC, a netbook computer, a
workstation, a server, a personal digital assistant (PDA), a
portable multimedia player (PMP), a MPEG-1 audio layer-3 (MP3)
player, a mobile medical device, a camera, and a wearable device.
According to various embodiments of the present disclosure, the
wearable device may include at least one of an accessory type
(e.g., a watch, a ring, a bracelet, an anklet, a necklace, a
glasses, a contact lens, or a head-mounted device (HMD)), a fabric
or clothing integrated type (e.g., an electronic clothing), a
body-mounted type (e.g., a skin pad, or tattoo), and a
bio-implantable type (e.g., an implantable circuit).
[0038] According to an embodiment, the electronic device may be a
home appliance. The home appliance may include at least one of, for
example, a television, a digital versatile disc (DVD) player, an
audio, a refrigerator, an air conditioner, a vacuum cleaner, an
oven, a microwave oven, a washing machine, an air cleaner, a
set-top box, a home automation control panel, a security control
panel, a TV box, a game console, an electronic dictionary, an
electronic key, a camcorder, and an electronic photo frame.
[0039] According to another embodiment, the electronic device may
include at least one of various medical devices (e.g., various
portable medical measuring devices (a blood glucose monitoring
device, a heart rate monitoring device, a blood pressure measuring
device, a body temperature measuring device, etc.), a magnetic
resonance angiography (MRA), a magnetic resonance imaging (MRI), a
computed tomography (CT) machine, and an ultrasonic machine), a
navigation device, a global positioning system (GPS) receiver, an
event data recorder (EDR), a flight data recorder (FDR), a vehicle
infotainment device, an electronic devices for a ship (e.g., a
navigation device for a ship, and a gyro-compass), avionics,
security devices, an automotive head unit, a robot for home or
industry, an automated teller machine (ATM) in banks, point of
sales (POS) device in a shop, or an Internet of things (IoT) device
(e.g., a light bulb, various sensors, electric or gas meter, a
sprinkler device, a fire alarm, a thermostat, a streetlamp, a
toaster, a sporting goods, a hot water tank, a heater, a boiler,
etc.).
[0040] According to some embodiments, the electronic device may
include at least one of a part of furniture or a
building/structure, an electronic board, an electronic signature
receiving device, a projector, and various kinds of measuring
instruments (e.g., a water meter, an electric meter, a gas meter,
and a radio wave meter). In various embodiments, the electronic
device may be a combination of one or more of the aforementioned
various devices. According to embodiment, the electronic device may
also be a flexible device. Further, the electronic device is not
limited to the aforementioned devices, and may include a new
electronic device according to the development of technology.
[0041] Herein, the term "user" may indicate a person using an
electronic device or a device (e.g., an artificial intelligence
electronic device) using an electronic device.
[0042] FIG. 1 is a flowchart illustrating a method for
manufacturing a plate using an aluminum alloy, according to an
embodiment.
[0043] Referring to FIG. 1, an aluminum plate used for an exterior
material or an interior material of the electronic device may be
manufactured according to a process method in which an aluminum
alloy material 110 is provided, in process 10; the provided
aluminum alloy material 110 is polished or a surface unevenness on
the provided aluminum alloy material is formed, in process 20; an
aluminum plate 130 is formed by anodizing the aluminum alloy
material 120 provided according to process 10, in process 30; and a
surface treatment is provided on the anodized aluminum alloy, in
process 40.
[0044] The aluminum alloy material 110 may be provided according to
process 10. The aluminum alloy material 110 may include, for
example, an alloy from a 2xxx series alloy to a high strength 7xxx
series alloy, excluding pure aluminum. For example, the aluminum
alloy material is mainly composed of aluminum, and major alloying
elements thereof include copper, magnesium, manganese, silicon,
tin, zinc, etc.
[0045] According to an embodiment, the provided aluminum alloy
material 110 may be an aluminum 6xxx series alloy. The aluminum
6xxx series alloy has a medium strength level among the aluminum
alloys and is excellent in corrosion resistance and weldability.
Further, the aluminum 6xxx series alloy may have good cold
workability through a heat treatment. In addition, some types of
alloys are excellent in anodizing property and extrusion
moldability.
[0046] The aluminum 6xxx series alloy used for the electronic
device may be an Al--Mg--Si alloy composed of aluminum (Al),
silicon (Si), and magnesium (Mg).
[0047] For example, the composition ratio of the aluminum 6xxx
series alloy with respect to the total weight thereof may be 96.00
to 98.50% of aluminum (Al), 0.2 to 1.0% of silicon (Si), and 0.4 to
1.2% of magnesium (Mg), and the aluminum 6xxx series may include at
least one unavoidable impurity. The at least one impurity may
include at least one of iron (Fe), copper (Cu), manganese (Mn),
chromium (Cr), zinc (Zn), and titanium (Ti). The impurities are
contained in trace amounts. For example, copper (Cu) may be
contained in the range of 0.15 to 1.1 wt %, chromium (Cr) may be
contained in the range of 0.04 to 0.35 wt %, zinc (Zn) may be
contained up to 0.25 wt %, and titanium (Ti) may be contained up to
0.15 wt %.
[0048] The aluminum 6xxx series alloy may be an Al 6063 alloy
having a yield strength of at least 200 MPa. As another example,
for the anodizing treatment, an Al--Mg--Si alloy containing 1 wt %
or less of copper (Cu) may be used.
[0049] After the aluminum alloy material 110 is provided, a
polishing process and/or a surface unevenness forming process may
be performed on the aluminum alloy material 110, according to
process 20.
[0050] The polishing process is performed so as to implement high
gloss on the surface of an aluminum plate to be applied to an
electronic device, and the polishing method may include a physical
polishing process and/or an electrolytic polishing process.
[0051] In the polishing process, an electrolytic polishing process
may be performed after the physical polishing process is performed.
As another example, the physical polishing process may be performed
after the electrolytic polishing process is performed. As a further
example, any one of a physical polishing process and an
electrolytic polishing process may be selected and performed.
[0052] A physical polishing (e.g., wheel-polishing) process may be
performed by bringing a rotating polishing tool into contact with
the surface of the aluminum alloy material 110. For example, the
polishing tool may be constructed by mounting a member capable of
causing physical friction, such as abrasive cloth, paper, leather,
or polymer, on a jig, which is movable in a horizontal direction
and/or a vertical direction.
[0053] The surface of the aluminum alloy material 110 seated on the
jig of the polishing tool may be polished by causing the polishing
cloth of the polishing tool to be rotated while pressing the
polishing cloth at a predetermined constant pressure. The
rotational speed and pressure of the polishing tool to be pressed
against the aluminum alloy material 110 can be variously changed
according to the setting of the user. In the physical polishing
process, a wet polishing method in which polishing is performed in
the state in which the surface of the aluminum alloy material 110
is wet and a dry polishing method in which polishing is performed
in the state in which the surface of the aluminum alloy material
110 is dry may be selectively used. As another example, the wet
polishing and the dry polishing may be performed in parallel.
[0054] A washing process may be included in a time period of
movement between polishing processes, a time period before the
polishing process, and/or a time period between multiple polishing
steps. The surface gloss of the aluminum alloy material 110 can be
more efficiently implemented through the washing process. For
example, the polishing process may be carried out two or three
times, and the washing process may be performed 3-4 times,
including a process to be applied between the polishing processes
or before the polishing processes. However, the number of polishing
processes to be performed and the number of washing processes to be
performed are not fixed, and the numbers of polishing processes and
washing processes to be performed may be adjusted by the user as
necessary for implementing an effective gloss on the aluminum
plate.
[0055] The aluminum plate, which has been subjected to the physical
polishing process, may have a value of 100 to 800 gloss unit (GU)
when measured with a 60-degree gloss meter. Hereinafter, in the
following examples, the contents of analysis of the gloss unit of
an aluminum plate, which has been subjected to the physical
polishing process, are provided.
[0056] Table 1 provides the contents of analysis of the gloss unit
through a 60-degree gloss meter after the physical polishing
process was performed using an aluminum 6xxx series alloy,
according to an embodiment.
TABLE-US-00001 TABLE 1 Surface Condition Average Max Min Embodiment
1 Performing Physical 732.6 748.9 717.7 Polishing Process
Embodiment 2 Performing Blasting 15.9 16.0 15.5
[0057] As shown in Table 1, the GU values are measured for
Embodiments 1 and 2 after performing different processes.
[0058] In Embodiment 1, GU values are measured after physical
polishing is performed on the surfaces of the provided aluminum
alloy materials 110 and 120.
[0059] As a result of performing the above physical polishing
process, the maximum GU value is measured as 748.9, and the minimum
GU value is measured as 717.7. The average GU value is 732.6.
[0060] In Embodiment 2, GU values are measured after blasting is
performed on the surfaces of provided aluminum alloy materials 110
and 120.
[0061] As a result of performing the blasting process, the maximum
GU value is measured as 16.0 and the minimum GU value is measured
as 15.5. The average GU value is 15.9.
[0062] From the analysis values by a surface glossmeter for the
aluminum plate 130 formed after different surface processes were
performed on the aluminum 6xxx series alloys of Embodiments 1 and
2, the aluminum plate 130, which was subjected to the physical
polishing process, can obtain a relatively high gloss compared with
the material, which was subjected to the blasting process.
[0063] An electrolytic polishing process may make the surface of
the aluminum alloy material 110 smooth and/or glossy using an
anodic dissolution phenomenon. For example, the electrolytic
polishing process may be performed in such a manner that the
aluminum alloy material 110 is accommodated in the electrolytic
polishing equipment together with an electrolytic solution and
protruding portions on the surface of the aluminum alloy material
110 are dissolved first.
[0064] The electrolytic polishing process may be performed while
causing DC current to flow in a manufactured electrolytic solution
using the aluminum alloy material 110 to be polished as an anode
and using a corresponding conductor (e.g., an insoluble and
electrically energizable plate) as a cathode. The electrolytic
solution may be made using an acid, such as phosphoric acid or
sulfuric acid, as a main component. In addition, various additives
may be added in order to prevent burning of a portion in which high
current flows. For example, at least one of sulphamate, a
chlorine-based oxidizing agent (e.g., ammonium chloride), acetic
acid, and glycerol, may be used as an additive. As another example,
the polishing tool may include a filter, an air agitator, a
mechanical agitator, etc. in order to remove a foreign substance
generated during the process.
[0065] The electrolytic polishing process may be performed with 10
to 50 V at a temperature ranging from a room temperature to
90.degree. C.
[0066] The surface unevenness forming process may be performed on
the aluminum alloy material 110 after a polishing process (e.g.,
physical polishing process and/or electrolytic polishing process)
may be performed on the aluminum alloy material 110. The surface
unevenness forming process may be performed after the physical
polishing process is performed, or may be performed after the
electrolytic polishing process is performed. As another example,
the surface unevenness forming process may be performed after the
physical polishing process and the electrolytic process are
sequentially performed, or may be performed in the state where the
polishing process is not performed.
[0067] The surface unevenness forming process is performed in order
to implement high gloss on the surface of the aluminum plate 130 to
be applied to the electronic device, and may include a method of
applying a physical force and/or a method of applying a chemical
force.
[0068] The aluminum plate 110, which has been subjected to the
surface unevenness forming process, may have values of 200 to 500
GU when measured with a 60-degree gloss meter.
[0069] A non-gloss anodizing process may be directly performed on
the provided aluminum alloy material 110, in addition to the
polishing process and/or the surface unevenness forming
process.
[0070] After the polishing process and/or the surface unevenness
forming process, the anodizing process may be performed on the
aluminum alloy material 120 in which the polishing is performed or
unevenness is formed, according to process 30. The anodizing
process may be performed after the polishing process is performed,
or may be performed after the surface unevenness forming process is
performed. As another example, the anodizing process may be
performed after the polishing process and the surface unevenness
forming process are sequentially performed, or may be performed in
the state in which the polishing process or the surface unevenness
forming process is not be performed.
[0071] The anodizing process may include pretreatment (cleaning),
anodizing, coloring, sealing, and elution processes. As another
example, the anodizing process may include pretreatment (cleaning),
anodizing, sealing, and elution processes performed using the
metallic color of the aluminum alloy material 110.
[0072] The anodizing process may be performed by providing an
apparatus configured to contain an electrolyte containing at least
one or all of sulfuric acid, oxalic acid, phosphoric acid, and
chromic acid, soaking the aluminum alloy materials 110 and 120 in
the electrolyte solution, and providing a predetermined voltage and
temperature.
[0073] The anodizing process may be performed at a temperature of
about 30.degree. C. or less and a voltage of about 10 V or less for
5 minutes or more. For example, the anodizing process may be
performed at a temperature ranging from 5 to 30.degree. C. and a
voltage ranging from 4 to V for 5 to 180 minutes. The anodizing
process may be performed using a voltage, which is relatively lower
than that used in a general anodizing process, through which a
relatively high-density film can be formed on the aluminum plate
10.
[0074] For example, referring to FIGS. 4A and 4B, compared with a
case in which an anodizing treatment is performed by applying a
conventional voltage (e.g., a voltage of 20 V or more (see FIG.
4A)) to the aluminum alloy material, when an anodizing treatment is
performed on the aluminum alloy material at a low voltage (e.g., a
voltage of 10 V or less (see FIG. 4B)), the range of the electric
field per unit area, which is applied to the surfaces of the
aluminum alloy materials 110 and 120, may be relatively reduced. As
a result, the number of regions of unit electric field formed per
unit area increases, and a film having pores with a small diameter
can be formed on each of the surfaces of the aluminum alloy
materials 110 and 120 in which the number of pores may be larger
than the number of pores which may be formed in a film obtained by
performing the conventional anodizing treatment.
[0075] The thickness of the film having many pores can be reduced
compared with a film formed at a high voltage, and thus, the pore
density can be increased accordingly. The surface having the
high-density film may generate many irregular reflections when
external light is incident on the aluminum plate, so that the
reflection on the surface can be increased, a ceramic-like texture
can be provided, and high gloss can be provided. The ceramic-like
texture may be provided in the form of a soft texture like a foggy
appearance generated on the anodized surface, for example. GU
values obtained using a 60-degree gloss meter and specific values
of the brightness (L), color (a), and saturation (b) obtained using
a color difference meter, according to an embodiment, are described
in greater detail below.
[0076] In the anodizing process, the coloring process may provide
various colors to the finished aluminum plate. As another example,
when the anodizing process, in which the coloring process is
excluded, is performed on the aluminum plate, it is possible to
provide a white color plate as a finished aluminum plate.
[0077] For example, when a coloring process is excluded from the
existing anodizing process performed on an aluminum plate, it is
impossible to implement white color because a metallic color
inherent in aluminum appears. An anodizing process using a
predetermined voltage generates films for providing a plurality of
reflected light beams in the state in which no material for
implementing a color tinge is added, so that a white color plate
can be provided.
[0078] Hereinafter, the details of the anodizing process are
described with reference to various examples.
[0079] FIG. 2 is a graph illustrating a gloss unit measured using
an anodizing 60-degree gloss meter for various values of voltage,
using an aluminum 6xxx series alloy, according to an embodiment of
the present disclosure. The information of FIG. 2 is also shown in
Table 2 below.
TABLE-US-00002 TABLE 2 V (voltage) Average Max Min Embodiment 1 8 V
263.3 266.4 258.4 Embodiment 2 10 V 248.0 254.6 240.5 Embodiment 3
12 V 171.7 175.2 167.0 Embodiment 4 14 V 135.7 138.5 133.5
[0080] As shown in FIG. 2 and Table 2, Embodiments 1 to 4 were
tested under different conditions.
[0081] In Embodiment 1, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 8 V for 5 to 180 minutes.
As a result of performing the anodizing treatment, the maximum GU
value is measured as 266.4, and the minimum GU value is measured as
258.4. The average GU value is 263.3.
[0082] In Embodiment 2, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 10V for 5 to 180 minutes.
As a result of performing the anodizing treatment, the maximum GU
value is measured as 254.6, and the minimum GU value is measured as
240.5. The average GU value is 248.0.
[0083] In Embodiment 3, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 12V for 5 to 180 minutes.
As a result of performing the anodizing treatment, the maximum GU
value is measured as 175.2, and the minimum GU value is measured as
167.0. The average GU value is 171.7.
[0084] In Embodiment 4, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 14V for 5 to 180 minutes.
As a result of performing the anodizing treatment, the maximum GU
value is measured as 138.5, and the minimum GU value is measured as
133.5. The average GU value is 135.7.
[0085] From the gloss meter analysis values using the aluminum
plate 130 obtained by anodizing an aluminum 6xxx series alloy in
Embodiments 1 to 4, it is shown that as the voltage is increased,
the GU values are decreased constantly. Accordingly, on the
aluminum plate 130, a relatively high gloss can be obtained by
using a predetermined voltage band in the anodizing treatment
compared to the existing voltage (e.g., the voltage of 20 V or
more).
[0086] FIGS. 3A to 3C are graphs illustrating color difference
meter values obtained using an aluminum 6xxx series alloy after
anodizing aluminum 6xxx series alloy at various voltage values,
according to embodiments. The information of FIGS. 3A to 3C is also
shown in Table 3 below. FIG. 3A shows a color difference meter
value of brightness (L), FIG. 3B shows a color difference meter
value of hue (a), and FIG. 3C shows a color difference meter value
of the saturation (b).
TABLE-US-00003 TABLE 3 V (voltage) a b L Embodiment 1 8 V -0.31
1.32 86.02 Embodiment 2 10 V -0.38 2.56 85.84 Embodiment 3 12 V
-0.59 3.94 84.13 Embodiment 4 14 V -0.77 5.49 82.34
[0087] As shown in FIGS. 3A to 3C and Table 3 above, color
difference meter values can be found through Embodiments 1 to 4.
Here, "L" indicates brightness, and "a" indicates red as the (+)
value thereof increases and green as the (-) value thereof
increases, and "b" indicates yellow as the (+) value thereof
increases and blue as the (-) value thereof increases.
[0088] In Embodiment 1, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 8 V for 5 to 180 minutes.
As the result of performing the anodizing treatment, the color
difference meter value of brightness (L) is 86.02. The color
difference meter value of hue (a) is -0.31, and the color
difference meter value of saturation (b) is 1.32.
[0089] In Embodiment 2, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 10V for 5 to 180 minutes.
As the result of performing the anodizing treatment, the color
difference meter value of brightness (L) is 85.84. The color
difference meter value of hue (a) is -0.38, and the color
difference meter value of saturation (b) is 2.56.
[0090] In Embodiment 3, the provided aluminum alloy materials 110
and 120 re anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 12V for 5 to 180 minutes.
As the result of performing the anodizing treatment, the color
difference meter value of brightness (L) is 84.13. The color
difference meter value of hue (a) is -0.59, and the color
difference meter value of saturation (b) is 3.94.
[0091] In Embodiment 4, the provided aluminum alloy materials 110
and 120 are anodized at a temperature ranging from 5 to 30.degree.
C. and at a voltage in the range of about 14V for 5 to 180 minutes.
As the result of performing the anodizing treatment, the color
difference meter value of brightness (L) is 82.34. The color
difference meter value of hue (a) is -0.77, and the color
difference meter value of saturation (b) is 5.49.
[0092] From the gloss meter analysis values obtained using the
aluminum plate 130 obtained by anodizing an aluminum 6xxx series
alloy in Embodiments 1 to 4, it is shown that as the voltage is
increased, a color difference meter value of brightness (L) is
decreased constantly. Accordingly, on the aluminum plate 130, a
white color aluminum plate can be obtained using a predetermined
voltage band in the anodizing treatment compared to the existing
voltage (e.g., the voltage of 20 V or more).
[0093] As another example, as the voltage is increased, the value
of hue (a) is decreased and the value of saturation (b) is
increased. For example, as the voltage is increased, a green tinge
and a yellow tinge are increased. Accordingly, the aluminum plate
has the value of hue (a) and the value of saturation (b), which are
close to zero through the voltage band used for the anodizing
process, an aluminum plate 130 having low saturation and a low-hue
color, so that a plate having a soft ceramic texture can be
manufactured.
[0094] After the anodizing process of the aluminum plate, a surface
treatment process may be performed on the aluminum plate 130,
according to process 40.
[0095] The surface treatment process may be performed by a coating
treatment method for protecting the surface of the aluminum plate
130. For example, the surface treatment process may include an
electrodeposition coating process, a coating process of a
high-hardness thin film including an organic and/or inorganic
hybrid resin, and a deposition process using a metal and an inert
gas. The electrodeposition coating, thin film coating, and
deposition processes of the surface treatment process may be
sequentially performed, and some of the processes may be excluded,
if necessary.
[0096] The electrodeposition coating process is a process of
immersing the anodized aluminum plate 130 in an electrodeposition
coating material so that the inner and outer surfaces of the
anodized aluminum plate 130 can be coated with electrodeposition
coating material. For example, the aluminum plate 130 may be placed
in a container in which a water-soluble resin coating material is
contained, and current may be supplied to the aluminum plate 130,
so that a coating film can be formed on the surface thereof. The
aluminum plate 130 can be coated by supplying current to a coating
material solution so as to use a phenomenon in which cation
particles move to a cathode and anion particles move to an
anode.
[0097] According to another example, the thin film coating process
is a process of coating the anodized aluminum plate 130 with, for
example, a polymer material, such as epoxy, acryl, or urethane. The
coated aluminum plate 130 may be subjected to a high-temperature
drying process in which the aluminum plate 130 is dried at a
temperature of about 80.degree. C. or more for about one hour or
more.
[0098] According to another example, the deposition process may be
performed using a principle in which positive ions are caused to
collide against a metal target such as titanium (Ti), silicon (Si),
or chromium (Cr) using plasma due to a phenomenon in which positive
ions are accelerated to a negative electrode.
[0099] The coating thickness of the aluminum plate 130, according
to the surface treatment process, may be variously implemented from
1 .mu.m to 30 .mu.m depending on a specification.
[0100] As another example, an anodizing process may be further
performed after the surface treatment process (process 40). The
anodizing treatment is the same as that described above, and thus,
a description thereof is omitted.
[0101] Hereinafter, the details of test processes will be described
with reference to various embodiments.
[0102] FIG. 4A is a diagram illustrating an enlarged schematic view
of a portion of the internal structure of an aluminum plate, which
has been subjected to a conventional anodizing treatment. FIG. 4B
is a diagram illustrating an enlarged schematic view of a portion
of the inner structure of an aluminum plate, which has been
subjected to an anodizing treatment, according to an
embodiment.
[0103] FIG. 5A is a diagram illustrating a schematic enlarged
perspective view of a portion (for a unit area S1) of the aluminum
plate of FIG. 4A, which has been subjected to a conventional
anodizing treatment. FIG. 5B is a diagram illustrating a schematic
enlarged perspective view of a portion (for a unit area S2) of the
aluminum plate of FIG. 4B, which has been subjected to an anodizing
treatment, according to an embodiment.
[0104] Aluminum plates 200 and 300 in FIGS. 4B and 5B may be
aluminum plates produced according to the aluminum plate
manufacturing method of FIG. 1
[0105] Referring to FIGS. 4A, 4B, 5A, and 5B, the aluminum plates
200 and 300 may be coated with a film having a large number of
pores 300a per unit area compared with the conventional aluminum
plates 20 and 30.
[0106] The anodizing process performed on the aluminum plates 200
and 300 may be conducted at a temperature of 30.degree. C. or less
and at a voltage of approximately 14 V or less for 5 minutes or
more. As another example, the anodizing process may be a process in
which the aluminum alloy material is treated at a temperature in
the range of 5 to 30.degree. C. and at a voltage ranging from 4 to
10 V for 5 to 180 minutes. The voltage used in the anodizing
process may be lower than the voltage used in the anodizing process
of a conventional aluminum alloy (e.g., 20 V or more).
[0107] The anodized aluminum plates 200 and 300 may be coated with
a film including pores 300a at a relatively higher density than
that coated on the conventionally anodized aluminum plates 20 and
30. For example, in comparison with the case where anodizing is
performed at a conventional voltage (e.g., the voltage of 20 V or
higher), when the anodizing process is performed at a low voltage
(e.g., a voltage lower than 14 V) on an aluminum 6xxx alloy
material, the range of the electric field applied per unit area S2
in a region of the surface of the aluminum plate 200 or 300 may be
reduced. Due to the reduction of the electric field, the size of a
unit electric field region formed per unit area S2 is reduced, and
the number of unit electric field regions can be increased.
[0108] In comparison with the conventional aluminum plates 20 and
30, the aluminum plates 200 and 300, according to an embodiment,
may have a large number of pores 200a and 300a per unit area, and
the size of the pores may be reduced. For example, while the number
of pores 30a formed per unit area S1 in the conventional aluminum
plates 20 and 30 may be two, the number of pores 300a formed per
unit area S2 in the aluminum plates 200 and 300 may be ten. The
pores 200a and 300a may be distributed over substantially the
entire area of the aluminum plates 200 and 300 and the pores 200a
and 300a may have a cylindrical or polygonal column shape. However,
this is merely an embodiment, and pores having various shapes may
be generated according to the conditions of the anodizing process,
and a design for the size and the number of pores may be
changed.
[0109] Since the aluminum plates 200 and 300 include a large number
of pores 200a and 300a per unit area S2 in comparison with the
conventional aluminum plates 20 and 30, the size of each of the
pores in the aluminum plates 200 and 300 may be small. For example,
the inner diameters 300b of the plurality of pores 200a and 300a
included in the anodized aluminum plates 200 and 300 may be
relatively smaller than the inner diameters 30b of the pores 20a 30
and 30a of the conventionally anodized aluminum plates 20 and
30.
[0110] Since the aluminum plates 200 and 300 include a large number
of pores 200a and 300a per unit area in comparison with
conventional aluminum plates 20 and 30, the interval 300c between
the pores may be relatively small. For example, the interval 300c
between the plurality of pores 200a and 300a included in the
anodized aluminum plates 200 and 300 may be relatively smaller than
the interval 30c between the pores 20a and 30a of the
conventionally anodized aluminum plates 20 and 30. The surface
region, which forms the interval 300c between the pores, may form
the outer surfaces of the aluminum plates 200 and 300 together with
the pores 200a and 300a and may be a region in which practically
external light is directly reflected.
[0111] FIG. 6A is a diagram illustrating a cross-sectional view
taken along line A-A' of an aluminum plate, which has been
subjected to a conventional anodizing treatment (excluding a
coloring process) of FIG. 5A. FIG. 6B is a diagram illustrating a
cross-sectional view of the aluminum plate 300 taken along the line
B-B' in FIG. 5B, which has been subjected to an anodizing treatment
(excluding a coloring process), according to an embodiment.
[0112] FIG. 7A is a diagram illustrating a cross-sectional view
taken along line A-A' of an aluminum plate, which has been
subjected to a conventional anodizing treatment (including a
coloring process) of FIG. 5A. FIG. 7B is a diagram illustrating a
cross-sectional view of the aluminum plate taken along the line
B-B' in FIG. 5B, which has been subjected to an anodizing treatment
(including a coloring process), according to an embodiment.
[0113] Aluminum plates 400 and 500 in FIGS. 6B and 7B may be
aluminum plates produced according to the aluminum plate
manufacturing method of FIG. 1.
[0114] Referring to FIGS. 6A and 6B, the aluminum plate 400 may be
coated with a film having a large number of pores 400a per unit
area in comparison with the conventional aluminum plate 40. As
another example, due to the large number of pores 400a per unit
area, the aluminum plate 400 may be manufactured such that the
interval 400c between the pores 400a is narrower in comparison with
those in the conventional aluminum plate 40. As a result, the
effect of causing irregular reflection due to external light can be
increased. For example, in the conventional structure, pores 40a
may be arranged at an interval 40c in the surface region where
irregular reflection occurs. In the structure according to an
embodiment, since a large number of pores 400a having a relatively
small inner diameter 400b may be arranged, the interval 400c of the
pores 400a in the surface region 400d may be smaller than the
interval 40c in the conventional aluminum plate 40c. Accordingly,
the regions where light is reflected may occur relatively densely,
and irregular reflection of light may at a closer interval than
that in the conventional structure.
[0115] The aluminum plates 40 and 400 of FIGS. 6A and 6B are
aluminum plates 40 and 400 manufactured through a pretreatment
(cleaning), anodizing, sealing, and elution processes during the
anodizing treatment. Since the coloring process is excluded from
the anodizing treatment, an aluminum plate having a color
arbitrarily added in addition to the metallic color of the metal
itself may be excluded.
[0116] The non-colored aluminum plate 400 may include a large
number of reflective portions 400d while having a relatively small
thickness 400c in comparison with a conventional non-colored
aluminum plate 40. Respective reflective portions 400d may extend
with respect to each other, and may form the outer surface of the
non-colored aluminum plate 400. According to an embodiment, the
reflective portions 400d are regions where irregular reflection
occurs due to light transmitted from the outside, and may variously
exhibit the gloss of the aluminum plate and the feeling of texture
imparted to the user.
[0117] Since a coloring chemical is relatively hardly infiltrated
into the pores 400a in the non-colored aluminum plate 400 in
comparison with the colored aluminum plate 500 to described later
(the colored aluminum plate 500 of FIG. 7), light-absorbing
portions are decreased, so that the reflected light can be further
increased.
[0118] The non-colored aluminum plate 400 may provide a white color
surface. For example, unlike conventional uncolored aluminum plate
40, in which the metallic color of the metal itself (e.g., silver
or gray) is implemented, the non-colored aluminum plate 400 may
cause countless irregular reflections through the increased pore
density and the reflective portions 400d, thereby providing a white
color surface. The surface, which provides the white color, may
provide an external appearance, which has an evenly soft texture
like a foggy appearance (e.g., an external appearance of a pastel
white tone, as described above) due to the large number of
irregular reflections.
[0119] Referring to FIGS. 7A and 7B, the aluminum plate 500 may be
coated with a film having a large number of pores 500a per unit
area in comparison with the conventional aluminum plate 50. The
aluminum plates 50 and 500 of FIGS. 7A and 7B are aluminum plates
50 and 500 manufactured through a pretreatment (cleaning),
anodizing, coloring, sealing, and elution processes during the
anodizing treatment. Through the coloring process in the anodizing
treatment, an aluminum plate having a color arbitrarily added in
addition to the metallic color of the metal itself may be
manufactured.
[0120] The colored aluminum plate 500 may include a large number of
reflective portions 500d while having a relatively small thickness
500c in comparison with a conventional colored aluminum plate 50.
Respective reflective portions 500d may extend with respect to each
other, and may form the outer surface of the colored aluminum plate
500. The reflective portions 500d are regions where irregular
reflection occurs due to light transmitted from the outside, and
may variously exhibit the gloss of the aluminum plate and the
feeling of texture imparted to the user.
[0121] Since a coloring chemical 500e is relatively easily
infiltrated into pores 500a in the colored aluminum plate 500 in
comparison with the non-colored aluminum plate 400, it is possible
to provide a variously colored surface having a pastel-tone texture
and gloss as described above.
[0122] FIG. 8A is an image obtained through SEM analysis by
capturing an anodized film obtained by applying a voltage of 14V
and then performing a FIB treatment of the anodized film, according
to an embodiment. FIG. 8B is an image obtained by through SEM
analysis capturing an anodized film obtained by applying a voltage
of 8V and then performing a FIB treatment of the anodized film,
according to an embodiment.
[0123] Referring to FIGS. 8A and 8B, the size of a plurality of
pores and intervals between the plurality of pores (e.g., walls) in
an aluminum plate, which has been subjected to an anodizing
treatment by applying a voltage of 14 V, and the size of a
plurality of pores and intervals between the plurality of pores an
aluminum plate, which has been subjected to an anodizing treatment
using a voltage of 8 V, are compared with each other.
[0124] When comparing sizes of the plurality of pores and the walls
in FIGS. 8A and 8B, the size including one pore and walls thereof
in the case of FIG. 8A is 0.45 to 1.1 .mu.m, while the size
including one pore and the walls thereof in the case of FIG. 8B is
0.3 to 0.55 .mu.m.
[0125] According to the results of analysis, compared with the case
where the anodizing treatment is performed at a conventional
voltage, when the anodizing treatment is performed on an aluminum
6xxx series alloy material at a relatively low voltage, the range
of the electric field applied per unit area in a region of the
surface of the aluminum plate may be reduced. Accordingly, in
comparison with the size of the inner diameter of pores in the
conventional anodized aluminum plate, the pores in the aluminum
plate, which was subjected to the anodizing treatment at a
relatively low voltage, may have a relatively small inner
diameter.
[0126] FIG. 9 is a diagram illustrating an exploded perspective
view of an electronic device that includes a display device
configured with an aluminum alloy, according to an embodiment.
[0127] Referring to FIG. 9, an electronic device 600 includes a
housing 610 having a front cover 611 facing a first direction (-Y)
and a rear cover 612 facing a second direction (+Y) opposite the
first direction of the front cover 611. The housing 610 may include
a transparent region that forms at least a portion of the front
cover. The electronic device 600 includes a display device 620 that
is disposed within the housing 610 and includes a screen region
exposed through the front cover 611. The housing 610 may be made of
an aluminum alloy capable of being anodized, and the aluminum alloy
may be configured as an exterior material or an interior material
including the above-mentioned aluminum 6xxx series alloy.
[0128] The housing 610 is configured to accommodate various
electronic components and the like, and at least a portion of the
housing 110 may be made of a conductive material. For example, the
housing 610 may include sidewalls forming the outer surface of the
electronic device 600. Alternatively, a portion of the housing 610,
which is exposed as the exterior of the electronic device 600, may
include a conductive material. Within the housing 610, a printed
circuit board 650 and/or a battery 660 may be accommodated. For
example, a processor, a communication module, various interfaces, a
power management module, or a control circuit may be configured in
the form of an integrated circuit chip, and may be mounted on the
printed circuit board 650. For example, the control circuit may be
a portion of the above-described processor or communication
module.
[0129] The display device 620 may be at least partially made of a
material that transmits radio waves or magnetic fields. For
example, the display device 620 may include a window member made of
a tempered glass material and a display panel mounted on the inner
surface of the window member. A touch panel may be mounted between
the window member and the display device. For example, the display
device 620 may be an output device for outputting a screen, and may
be used as an input device equipped with a touch screen
function.
[0130] As described above and according to an embodiment, a method
for manufacturing an anodizable aluminum plate includes a process
of providing an aluminum alloy material, and a process of
performing an anodizing treatment on the provided alloy material at
a temperature in a range of 5 to 30.degree. C. and at a voltage of
4 to 14 V for 5 to 180 minutes.
[0131] The anodizing process may include anodizing the provided
alloy material at a temperature in a range of 5 to 30.degree. C.
and at a voltage of 4 V to 10 V for 5 to 180 minutes.
[0132] The process of performing the anodizing treatment may
include a pretreatment process, an anodizing process, a sealing
process, and an elution process.
[0133] The process of performing the anodizing treatment may
include a pretreatment process, an anodizing process, a coloring
process, a sealing process, and an elution process.
[0134] After the process of providing the aluminum alloy material,
the method may further include a process of polishing the provided
alloy material or a process of forming surface unevenness.
[0135] The process of polishing the aluminum alloy material may
include a physical polishing process of wet- or dry-polishing the
surface of the aluminum alloy material, and the aluminum plate,
which have been subjected to the physical polishing process, may
have a 60-degree gloss meter value of 100 to 800 GU.
[0136] The process of polishing the aluminum alloy material may
include an electrolytic polishing step of polishing the aluminum
material at a temperature ranging from a room temperature to
90.degree. C. and at a voltage of 10 to 50 V.
[0137] The aluminum alloy material on which the electrolytic
polishing process has been performed may have a 60-degree gloss
meter value of 200 to 500 GU.
[0138] The anodized aluminum plate includes a plurality of pores,
the length of the cross-section of a structure including at least
one pore and the walls surrounding the pore is from 0.30 to 0.55
.mu.m, and a 60-degree gloss meter value of the anodized aluminum
plate may be 200 GU or more.
[0139] The anodized aluminum plate may have a color difference
meter value of brightness (L) of 85.00 or more.
[0140] The anodized aluminum plate may have a color difference
meter value of hue (a) of -0.40 or more and a color difference
meter value of saturation (b) of 3.00 or less.
[0141] A surface treatment process for protecting the anodized
surface by performing coating on the surface of the anodized plate
may be further included after the process of performing the
anodizing treatment on the aluminum alloy material.
[0142] The surface treatment process may include at least one of
electrophoretic coating, a process of coating a high-hardness thin
film including an organic and/or inorganic hybrid resin, and a
deposition process using a metal and an inert gas.
[0143] According to an embodiment, an anodizable aluminum plate may
have a 60-degree gloss meter value of at least 120 GU through the
anodizing treatment using a voltage of 4 V to 10 V.
[0144] The anodized aluminum plate may include a plurality of
pores, and the length of a cross-section of a structure including
at least one pore and walls surrounding the pore may be 0.30 to
0.55 .mu.m.
[0145] A 60-degree gloss meter value of the anodized aluminum plate
may be 200 GU or more.
[0146] The aluminum plate may include a white color which has a
color difference meter value of brightness (L) of 85.00 or
more.
[0147] The aluminum plate may include a white color which has a
color difference meter value of hue (a) of -0.40 or more.
[0148] The aluminum plate may include a white color which has a
color difference meter value of saturation (b) of 3.00 or less.
[0149] The aluminum plate includes an aluminum 6xxx series alloy,
and the aluminum 6xxx series alloy may include 0.2-1.0 wt % of
silicon (Si), 0.4-1.2 wt % of magnesium (Mg), and a balance
including aluminum (Al) and at least one inevitable impurity.
[0150] The at least one impurity of the aluminum 6xxx series alloy
may be at least one of iron (Fe), copper (Cu), manganese (Mn),
chromium (Cr), zinc (Zn), and titanium (Ti).
[0151] According to an embodiment, an electronic device is provided
including an exterior material made of an aluminum alloy. The
electronic device may include a housing including a front cover
facing a first direction and a rear cover facing a second direction
opposite the first direction, and including a transparent region,
which forms at least a portion of the front cover, and a display
device disposed in the housing and including a screen region
exposed through the front cover. The housing may include an
aluminum 6xxx series alloy, and may have a 60-degree gloss meter
value of at least 120 GU through an anodizing treatment using a
voltage of 4 V to 10 V.
[0152] According to an embodiment, it is possible to implement a
surface having a ceramic texture, which is highly demanded in
design, in addition to a metal texture by anodizing an aluminum
alloy. Thus, it is possible to provide a plate, which has a
beautiful appearance.
[0153] According to an embodiment, it is possible to provide a
high-gloss white color plate through a simple process in which an
additional coloring process is not performed.
[0154] According to an embodiment, it is possible to implement a
plate having various colors and a high-gloss ceramic texture.
[0155] According to an embodiment, it is possible to provide a
plate having a soft pastel-tone by manufacturing, through an
anodizing treatment, where the plate has a surface with countless
irregular reflections.
[0156] While the present disclosure has been shown and described
with reference to certain embodiments thereof, it will be
understood by those skilled in the art that various changes in form
and detail may be made therein without departing from the spirit
and scope of the disclosure as defined by the appended claims.
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