U.S. patent application number 15/554589 was filed with the patent office on 2018-03-15 for fiber-reinforced resin structure and method for producing fiber-reinforced resin structure.
This patent application is currently assigned to TOCALO CO., LTD.. The applicant listed for this patent is TOCALO CO., LTD.. Invention is credited to Naoki ABE, Yoichiro HABU, Tatsuya HAMAGUCHI, Yasuo MIYAKE.
Application Number | 20180073121 15/554589 |
Document ID | / |
Family ID | 56848946 |
Filed Date | 2018-03-15 |
United States Patent
Application |
20180073121 |
Kind Code |
A1 |
HABU; Yoichiro ; et
al. |
March 15, 2018 |
FIBER-REINFORCED RESIN STRUCTURE AND METHOD FOR PRODUCING
FIBER-REINFORCED RESIN STRUCTURE
Abstract
[Task] It is to provide a fiber-reinforced resin structure
having improved surface properties and reinforced with carbon
fibers or glass fibers while keeping lightweight properties.
[Solution] A fiber-reinforced resin structure is constructed by
forming a thermal sprayed coating composed mainly of boron carbide
on a fiber-reinforced plastic substrate as a top coating.
Inventors: |
HABU; Yoichiro; (Miyagi,
JP) ; MIYAKE; Yasuo; (Hyogo, JP) ; ABE;
Naoki; (Miyagi, JP) ; HAMAGUCHI; Tatsuya;
(Chiba, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TOCALO CO., LTD. |
Hyogo |
|
JP |
|
|
Assignee: |
TOCALO CO., LTD.
Hyogo
JP
|
Family ID: |
56848946 |
Appl. No.: |
15/554589 |
Filed: |
March 2, 2016 |
PCT Filed: |
March 2, 2016 |
PCT NO: |
PCT/JP2016/056357 |
371 Date: |
August 30, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B 9/00 20130101; C08J
7/0423 20200101; C23C 4/06 20130101; C23C 4/02 20130101; C23C 28/00
20130101; C23C 4/10 20130101 |
International
Class: |
C23C 4/10 20060101
C23C004/10; C23C 4/02 20060101 C23C004/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 4, 2015 |
JP |
2015-042075 |
Claims
1. A fiber-reinforced resin structure comprising a fiber-reinforced
plastic substrate and a thermal sprayed coating formed thereon and
composed mainly of boron carbide as a top coating.
2. The fiber-reinforced resin structure according to claim 1,
wherein the fiber-reinforced plastic substrate is a carbon
fiber-reinforced plastic substrate.
3. The fiber-reinforced resin structure according to claim 1,
wherein an intermediate layer A made from a metal is disposed
between the substrate and the top coating.
4. The fiber-reinforced resin structure according to claim 3,
wherein the metal is a simple substance selected from aluminum,
titanium and magnesium or an alloy containing one or more of these
elements.
5. The fiber-reinforced resin structure according to claim 1,
wherein an intermediate layer A made from a ceramic is disposed
between the substrate and the top coating.
6. The fiber-reinforced resin structure according to claim 5,
wherein the ceramic is one or more oxide ceramics selected from
aluminum oxide, zirconium oxide, yttrium oxide, silicon oxide,
magnesium oxide, chromium oxide and titanium oxide.
7. The fiber-reinforced resin structure according to claim 1,
wherein the fiber-reinforced resin structure is provided with an
intermediate layer A made from a mixture of a resin and ceramic
particles between the substrate and the top coating.
8. The fiber-reinforced resin structure according to claim 7,
wherein the resin contained in the intermediate layer A includes a
resin of the same kind as the resin contained in the substrate.
9. The fiber-reinforced resin structure according to claim 7,
wherein at least a part of the melted and solidified resins is
integrally formed at a boundary face between the fiber-reinforced
plastic substrate and the intermediate layer A.
10. The fiber-reinforced resin structure according to claim 7,
wherein the ceramic particles contained in the intermediate layer A
are oxide ceramic particles containing one or more selected from
aluminum oxide, zirconium oxide, yttrium oxide, silicon oxide,
magnesium oxide, chromium oxide and titanium oxide.
11. The fiber-reinforced resin structure according to claim 3,
wherein the fiber-reinforced resin structure is provided with an
intermediate layer B made from one or more materials selected from
ceramic, metal and alloy between the intermediate layer A and the
top coating.
12. The fiber-reinforced resin structure according to claim 11,
wherein the intermediate layer B is a layer made from one or more
oxide ceramics selected from aluminum oxide, zirconium oxide,
yttrium oxide, silicon oxide, magnesium oxide, chromium oxide and
titanium oxide.
13. A method for producing a fiber-reinforced resin structure as
claimed in claim 1, characterized in that the top coating is formed
by a controlled atmosphere thermal spraying process.
14. The fiber-reinforced resin structure according to claim 5,
wherein the fiber-reinforced resin structure is provided with an
intermediate layer B made from one or more materials selected from
ceramic, metal and alloy between the intermediate layer A and the
top coating.
15. The fiber-reinforced resin structure according to claim 7,
wherein the fiber-reinforced resin structure is provided with an
intermediate layer B made from one or more materials selected from
ceramic, metal and alloy between the intermediate layer A and the
top coating.
16. The fiber-reinforced resin structure according to claim 14,
wherein the intermediate layer B is a layer made from one or more
oxide ceramics selected from aluminum oxide, zirconium oxide,
yttrium oxide, silicon oxide, magnesium oxide, chromium oxide and
titanium oxide.
17. The fiber-reinforced resin structure according to claim 15,
wherein the intermediate layer B is a layer made from one or more
oxide ceramics selected from aluminum oxide, zirconium oxide,
yttrium oxide, silicon oxide, magnesium oxide, chromium oxide and
titanium oxide.
Description
TECHNICAL FIELD
[0001] This invention relates to a fiber-reinforced resin structure
formed by applying surface properties to a fiber-reinforced plastic
substrate such as carbon fiber-reinforced plastic, glass
fiber-reinforced plastic or the like and a method for producing the
same.
RELATED ART
[0002] Materials such as carbon fiber-reinforced plastic, glass
fiber-reinforced plastic and so on are small in the specific
gravity as compared to a metal material or the like and have
features that a longitudinal elasticity modulus is high and
particularly a specific strength is excellent. Such
fiber-reinforced plastic materials are widely used in a field of
engineering material such as material for machine parts of
airplanes, automobiles and so on, or material for sport goods such
as fishing rods and so on.
[0003] The fiber-reinforced plastic substrates have excellent
characteristics as a strength member for structures, but actually
there are many issues to be overcome in the surface properties. For
instance, the surface of the substrate is substantially composed
mainly of a resin (epoxy resin or the like) though the fibers are
dispersed therein, so that abrasion resistance property is
insufficient. Furthermore, the heat resistance of the substrate
surface is dependent on the heat resistance of the resin itself, so
that service temperature thereof is critical.
[0004] In order to overcome the aforementioned problems of the
reinforced plastic substrates, there have hitherto been proposed a
method of applying an oxide ceramic such as alumina,
alumina/titania or the like to the surface by a thermal spraying
process and a method of applying a metallic Ni or Ni--P plated
coating to the surface through a plating method. However, the
former method is lacking in the adhesion force to the substrate,
while the latter method is remarkably lacking in the abrasion
resistance due to the rigidity, which are issues to be
overcome.
[0005] As to the lacking of the adhesion force, there is a proposal
of arranging an intermediate layer to enhance an adhesion force
between a substrate and a thermal sprayed coating (Patent Document
1), but it is not considered to join the inserted fibers to the
thermal sprayed coating. As a proposal for improving the abrasion
resistance in the latter method are described, for example, a
method of forming an non-electrolytic plating layer on a surface of
a roll pipe made from the fiber-reinforced plastic substrate
(Patent Document 2) and a method of applying a composite plating
later containing fluorine resin particles onto the surface of the
roll pipe made from the fiber-reinforced plastic substrate (Patent
Document 3), but these methods are actually unsatisfactory.
[0006] As a plastic-based composite material reinforced with carbon
fibers or glass fibers being excellent in the surface properties
such as abrasion resistance, heat resistance and the like, there
are newly proposed (i) a plastic-based composite material being
excellent in the surface properties such as abrasion resistance and
so on obtained by forming a thermal sprayed coating layer made from
an oxide ceramic or a cermet thereof as a top coating onto the
surface of the fiber-reinforced plastic substrate through an
intermediate layer made from a mixture of a resin of the same kind
as the resin constituting the substrate and ceramic particles
(Patent Document 4) and (ii) a plastic-based composite material
being excellent in the surface properties such as abrasion
resistance and so on obtained by forming a thermal sprayed coating
layer made from a carbide cermet as a top coating onto the surface
of the fiber-reinforced plastic substrate through an intermediate
layer made from a mixture of a resin of the same kind as the resin
constituting the substrate and ceramic particles (Patent Document
5).
PRIOR ART DOCUMENTS
Patent Documents
[0007] Patent Document 1: JP-A-H02-26875
[0008] Patent Document 2: JP-A-H05-286058
[0009] Patent Document 3: JP-A-H04-292634
[0010] Patent Document 4: JP-A-2001-240953
[0011] Patent Document 5: JP-A-2001-270015
[0012] Patent Document 6: JP-A-2000-178709
SUMMARY OF THE INVENTION
Task to be Solved by the Invention
[0013] When the oxide ceramic such as Al.sub.2O.sub.3 or the like
or the carbide cermet such as WC or the like is sprayed onto the
intermediate layer formed on the surface of the fiber-reinforced
plastic substrate, the adhesion force is improved, but there is
caused a new issue that the surface properties are not sufficient
or the weight is increased though the surface properties are
improved. As a result, it is actual that the properties inherent to
the fiber-reinforced plastic substrate having a light weight and a
rigidity cannot be developed.
[0014] The invention is made for solving the aforementioned
problems of the conventional techniques and an object thereof is to
provide a fiber-reinforced resin structure having improved surface
properties and reinforced with carbon fibers or glass fibers while
keeping lightweight properties.
Solution for Task
[0015] The inventors have made studies for achieving the above
object and found that a fiber-reinforced resin structure having the
following construction is an effective solution means, and hence
the invention has been accomplished. That is, the invention is a
fiber-reinforced resin structure comprising a fiber-reinforced
plastic substrate and a thermal sprayed coating formed thereon and
composed mainly of boron carbide as a top coating.
[0016] Also, the inventors propose the followings as an improved
embodiment of the fiber-reinforced resin structure.
[0017] (1) The fiber-reinforced plastic substrate is a carbon
fiber-reinforced plastic substrate.
[0018] (2) An intermediate layer A made from a metal is disposed
between the substrate and the top coating.
[0019] (3) The metal is a simple substance selected from aluminum,
titanium and magnesium or an alloy containing one or more of these
elements.
[0020] (4) An intermediate layer A made from a ceramic is disposed
between the substrate and the top coating.
[0021] (5) The ceramic is one or more oxide ceramics selected from
aluminum oxide, zirconium oxide, yttrium oxide, silicon oxide,
magnesium oxide, chromium oxide and titanium oxide.
[0022] (6) The fiber-reinforced resin structure is provided with an
intermediate layer A made from a mixture of a resin and ceramic
particles between the substrate and the top coating.
[0023] (7) The resin contained in the intermediate layer A includes
a resin of the same kind as the resin contained in the
substrate.
[0024] (8) At least a part of the melted and solidified resins is
integrally formed at a boundary face between the fiber-reinforced
plastic substrate and the intermediate layer A.
[0025] (9) The ceramic particles contained in the intermediate
layer A are oxide ceramic particles containing one or more selected
from aluminum oxide, zirconium oxide, yttrium oxide, silicon oxide,
magnesium oxide, chromium oxide and titanium oxide.
[0026] (10) The fiber-reinforced resin structure is provided with
an intermediate layer B made from one or more materials selected
from ceramic, metal and alloy between the intermediate layer A and
the top coating.
[0027] (11) The intermediate layer B is a layer made from one or
more oxide ceramics selected from aluminum oxide, zirconium oxide,
yttrium oxide, silicon oxide, magnesium oxide, chromium oxide and
titanium oxide.
[0028] (12) The top coating is formed by a controlled atmosphere
thermal spraying process.
[0029] Moreover, Patent Document 6 is known as a technique of
thermal spraying boron carbide though it is not an example of using
the fiber-reinforced plastic material as the substrate.
Effect of the Invention
[0030] As mentioned above, according to the invention, the thermal
sprayed coating composed mainly of boron carbide is formed on the
fiber-reinforced plastic substrate as a top coating, so that the
surface properties can be improved while keeping the lightweight
properties.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a schematically section view of a fiber-reinforced
resin structure according to the invention.
[0032] FIG. 2 is a graph showing results of a test for a resistance
to slurry erosion in Examples.
EMBODIMENTS FOR CARRYING OUT THE INVENTION
[0033] Embodiments according to the invention will be described in
detail below, but the invention is not limited thereto.
[0034] The fiber-reinforced resin structure according to the
invention is constructed by using fiber-reinforced plastics such as
carbon fiber-reinforced plastics (CFRP) and glass fiber-reinforced
plastics (GFRP) as a substrate and forming a coating having
excellent surface properties thereon. From a viewpoint of the
strength, the fiber-reinforced plastics are preferable to be carbon
fiber-reinforced plastics (CFRP).
[0035] As the fiber-reinforced plastic substrate can be used a
resin for a reinforced plastic and a reinforcing material in a
proper combination in accordance with use purpose and performances
required. For example, glass fibers and carbon fibers are important
as the reinforcing material, but inorganic material such as
whisker, asbestos, and mica, various other fibers such as aramid
fibers, cotton, linen, rayon, vinylon, Tetron (registered trade
mark), acryl and so on may be used. As a synthetic resin being a
matrix is preferably used a thermosetting resin such as polyester
resin, epoxy resin, phenolic resin (bakelite), furan resin or the
like. Also, a thermoplastic resin such as polypropylene, polyamide,
polyimide, polycarbonate, polyethylene terephthalate (PET) or the
like is used preferably. They are shaped into a given form by a
prepreg process, a winding process or the like to provide a
substrate.
[0036] It is preferable that the fiber-reinforced plastic substrate
and an intermediate layer mentioned later are roughened by lightly
grinding with a grinding material such as alumina particles or the
like prior to the subsequent formation of a coating layer. If the
carbon fiber-reinforced plastic or glass fiber-reinforced plastic
substrate is subjected to a strong roughening, however, the surface
form of the substrate itself is frequently damaged, so that it is
important to perform a light blasting treatment.
[0037] An intermediate layer is preferable to be formed on the
fiber-reinforced plastic substrate. The function of the
intermediate layer lies in not only a connection or an adhesive for
ensuring a good adhesiveness to a desired coating layer (for
example, a top coating) formed on the substrate but also reduction
of heat transferred to the substrate in the formation of the
coating layer. Since a heat-resistant temperature of the carbon
fiber-reinforced plastics (CFRP) as a general-purpose good is about
120.degree. C., it is preferable to form an intermediate layer for
shielding heat from exterior in order that the temperature of the
substrate does not exceed the above value. This is a point largely
different from a case of using a carbon material capable of
withstanding to a higher temperature of not lower than 2000.degree.
C. such as C/C composite (carbon-fiber reinforced carbon
composite).
[0038] The intermediate layer may be a single layer or plural
layers. In the case of forming the plural layers, functions of the
layers can be divided by providing each of the layers with
different properties. The number of the intermediate layers is not
limited.
[0039] As a material used in the intermediate layer, a light metal
is preferable as a metal, and an oxide ceramic is preferable as a
ceramic. As the light metal are mentioned a simple substance
selected from aluminum (Al), titanium (Ti) and magnesium (Mg) or an
alloy containing one or more of these elements. As the oxide
ceramic are mentioned one or more selected from aluminum oxide
(Al.sub.2O.sub.3), zirconium oxide (ZrO.sub.2), yttrium oxide
(Y.sub.2O.sub.3), silicon oxide (SiO.sub.2), magnesium oxide (MgO),
chromium oxide (Cr.sub.2O.sub.3) and titanium oxide
(TiO.sub.2).
[0040] When the intermediate layer is composed of plural layers, a
layer having a good affinity with the substrate is selected as a
layer located nearer to the substrate (e.g. a layer coating the
surface of the substrate) for ensuring the adhesiveness to the
substrate. To this end, the intermediate layer is preferable to be
made from a mixture of a resin and ceramic particles, and the resin
is preferable to be the same kind as the resin contained in the
substrate. Also, the ceramic particles are preferable to be oxide
ceramic particles containing one or more selected from aluminum
oxide (Al.sub.2O.sub.3), zirconium oxide (ZrO.sub.2), yttrium oxide
(Y.sub.2O.sub.3), silicon oxide (SiO.sub.2), magnesium oxide (MgO),
chromium oxide (Cr.sub.2O.sub.3) and titanium oxide (TiO.sub.2).
Such oxide ceramic particles are mixed and dispersed into the
resin, whereby the conduction of heat to the substrate can be
prevented in the formation of the top coating through thermal
spraying. These materials are relatively light in the weight and do
not damage the merits of the fiber-reinforced plastic
substrate.
[0041] The thickness of the intermediate layer is preferable to be
50-500 .mu.m. Also, the average particle size of the ceramic
particles is preferable to be 10-100 .mu.m. For example, a mixing
ratio (volume ratio) of the resin ingredient and ceramic particles
in the intermediate layer is resin:ceramic particles=1:9-7:3,
preferably 2:8-4:6. By using such a mixing ratio is easily made the
dispersion state of the particles uniform. Moreover, the blending
construction of both the materials may be a gradient blending
wherein the resin ingredient is made larger at the side of the
substrate and the ceramic particles are made larger at the side of
the top coating, or may be a stepwise changing blending.
[0042] When the intermediate layer is constructed with plural
layers, a layer located nearer to the top coating (for example, a
layer located just below the top coating) is preferable to be a
layer made from one or more materials selected from ceramic, metal
and alloy. Thus, heat is hardly transferred to the substrate and a
layer located just above thereof in the formation of the top
coating through thermal spraying. In this case, the intermediate
layer is preferable to be a layer of an oxide ceramic containing
one or more selected from aluminum oxide (Al.sub.2O.sub.3),
zirconium oxide (ZrO.sub.2), yttrium oxide (Y.sub.2O.sub.3),
silicon oxide (SiO.sub.2), magnesium oxide (MgO), chromium oxide
(Cr.sub.2O.sub.3) and titanium oxide (TiO.sub.2). They are material
of light weight having a heat shielding property and do not damage
the merits of the fiber-reinforced plastic substrate.
[0043] When the intermediate layer is a single layer, it is
preferable that the intermediate layer is a layer made from a
mixture of a resin and ceramic particles for the same reason as
mentioned above, and the resin is preferable to include the same
kind as the resin contained in the substrate. Also, the ceramic
particles are preferable to be oxide ceramic particles containing
one or more selected from aluminum oxide (Al.sub.2O.sub.3),
zirconium oxide (ZrO.sub.2), yttrium oxide (Y.sub.2O.sub.3),
silicon oxide (SiO.sub.2), magnesium oxide (MgO), chromium oxide
(Cr.sub.2O.sub.3) and titanium oxide (TiO.sub.2).
[0044] At the boundary face between fiber-reinforced plastic
substrate and the intermediate layer, it is preferable that the
resins are melted and solidified and at least a part thereof is
united integrally. Such an integrally united site can be formed by
forming the intermediate layer and then firing the intermediate
layer in the atmosphere at a temperature of 50-120.degree. C. for
about 1-10 hours. Thus, the resin in the substrate and the resin in
the intermediate layer are fused and rigidly adhered to each
other.
[0045] The intermediate layer can be formed by PVD process, CVD
process, thermal spraying process, a spray process using compressed
air and so on. In the case of forming a compact thin film, a PVD
process, CVD process or spray process using compressed air is
preferable, while in the case of ensuring a thickness, a thermal
spraying process or spray process using compressed air is
preferable.
[0046] In the invention, a thermal sprayed coating composed mainly
of boron carbide (B.sub.4C) is formed as a top coating. Thus,
desirable surface properties can be applied without damaging
lightweight properties as a merit of the fiber-reinforced plastic
substrate. In the specification of this application, the term "main
ingredient" means an ingredient contained in the largest amount by
a molar basis. The purity of boron carbide (B.sub.4C) is preferably
not less than 90 mol %, more preferably not less than 95 mol %,
further preferably not less than 99 mol %. The thermal sprayed
coating is preferable to have a porosity of 0.1-10%. The thermal
sprayed coating attains the securement of the thickness and can be
formed on a complicated form different from a PVD or CVD coating.
Particularly, the top coating to be formed is required to have a
thickness equal to or larger than a given value so as to be used
for a long time, which can be attained by the thermal sprayed
coating of boron carbide (B.sub.4C). Even if the thickness is made
thicker, there is no fear of increasing the weight. Furthermore,
when the aforementioned intermediate layer is applied to the
substrate, the transfer of heat to the substrate can be prevented
during thermal spraying. From the above, the combination of the
fiber-reinforced plastic substrate and the boron carbide (B.sub.4C)
thermal sprayed coating is particularly excellent.
[0047] When boron carbide (B.sub.4C) is used as a spraying
material, it is preferable to be in a particle shape, for example,
in an average particle size of 10-120 .mu.m. The thickness of the
thermal sprayed coating composed mainly of boron carbide (B.sub.4C)
is, for example, 50-700 .mu.m, preferably 100-500 .mu.m.
[0048] After the formation of the thermal sprayed coating, an
impregnation treatment with a sealer may be conducted for the
purpose of plugging pores in the coating. As the sealer can be used
an inorganic one or an organic polymer.
[0049] Specifically, the thermal sprayed coating composed mainly of
boron carbide (B.sub.4C) has surface properties such as resistance
to slurry erosion, resistance to blast erosion, abrasion
resistance, oxidation resistance, strength, hardness and so on
equal to or higher than those of the other ceramic or cermet
thermal sprayed coatings. No material has been found which has a
lighter weight than that of boron carbide (B.sub.4C) among spraying
materials which can be sprayed onto the fiber-reinforced plastic
substrate and can apply surface properties equal to those of boron
carbide (B.sub.4C). In the following Table 1 are shown specific
gravities of boron carbide (B.sub.4C) and the other main spraying
materials.
TABLE-US-00001 TABLE 1 Spraying material Specific gravity WC cermet
13.5 Al.sub.2O.sub.3 3.9 Cr.sub.2O.sub.3 5.2 Cr.sub.3C.sub.2 6.7
ZrO.sub.2 6.0 Ni-based alloy 9.0 Hard Cr plating material 6.9-7.1
B.sub.4C 2.5
[0050] As a thermal spraying process for the formation of the top
coating are mentioned atmospheric plasma spraying, low pressure
plasma spraying, controlled atmosphere thermal spraying, gas
combustion flame spraying and so on. Among them, the controlled
atmosphere thermal spraying is particularly preferable. The
controlled atmosphere thermal spraying is a process of performing
the thermal spraying in an atmosphere having a larger ratio of a
certain ingredient. By controlling a ratio of a gas other than
oxygen such as nitrogen gas or argon gas to not less than 95%,
preferably not less than 99% can be prevented oxidation of the
spraying material during thermal spraying to improve the properties
of the coating.
[0051] The thus formed fiber-reinforced resin structure has, for
example, a cross-section as shown in FIG. 1. In the example of FIG.
1, the fiber-reinforced resin structure 10 comprises a
fiber-reinforced plastic substrate 1 and a top coating 4 formed on
the substrate 1 and made of a thermal sprayed coating composed
mainly of boron carbide. Moreover, the example of FIG. 1 is a
preferable example of the invention, wherein the fiber-reinforced
resin structure 10 is formed by providing an intermediate layer 2
on the substrate 1 (intermediate layer A) and an intermediate layer
3 thereon (intermediate layer B) between the substrate 1 and the
top coating 4.
[0052] As a use application of the fiber-reinforced resin structure
according to the invention are mentioned a fan blade of an engine
for an airplane, a turbine blade of a compressor for airplane
engine, members in a primary wing and a fuselage of an airplane and
a mold used for the manufacture thereof, a turbine blade for a
steam turbine, a roll for the manufacture of a paper film, a
pressure vessel, a transfer member for semiconductor wafers and FPD
substrates, automobile parts, solar buttery members or flames for
space equipment, members for wind power generation, inner tube for
a chimney, parts for Shinkansen bullet trains and rail vehicles,
and so on.
EXAMPLES
Example 1
[0053] This example reports test results on a resistance to slurry
erosion in a structure formed by applying a B.sub.4C thermal
sprayed coating to a carbon fiber-reinforced plastic (CFRP)
substrate (Example 1).
[0054] There is first provided a CFRP substrate (substrate 1) of 50
mm.times.50 mm having a thickness of 5 mm using an epoxy-based
resin as a binder. Subsequently, it is ground with a surface
grinder for correcting the flatness thereof.
[0055] A mixture of 40 vol % of an epoxy-based resin and 60 vol %
of zirconium oxide (ZrO.sub.2) particles (average particle size: 35
.mu.m) is applied onto a surface to be coated with a compressed air
driving gun as a coating having a thickness of 150 .mu.m to form an
underlying intermediate layer (intermediate layer 2).
[0056] After the formation of the underlying intermediate layer
(intermediate layer 2), a sample (CFRP substrate 1/intermediate
layer 2) is inserted into an electric furnace to perform firing in
air at 100.degree. C. for 4 hours.
[0057] Next, a mixture of 78 wt % of aluminum oxide
(Al.sub.2O.sub.3) and 22 wt % of silicon oxide (SiO.sub.2) is
sprayed onto a surface to be coated with an atmospheric plasma
spraying device as a coating having a thickness of 100 .mu.m to
form an upper intermediate layer (intermediate layer 3).
[0058] Thereafter, B.sub.4C spraying material (average particle
size: 26 .mu.m) is sprayed under a controlled nitrogen atmosphere
of 99.995% with a controlled atmosphere thermal spraying machine to
form a coating having a thickness of 120 .mu.m as an outermost
layer (top coating 4).
[0059] After the coating treatment, the same epoxy-based resin as
in the underlying intermediate layer (intermediate layer 2) is
impregnated into the B.sub.4C thermal sprayed coating as an
outermost layer (top coating 4), which is placed in an electric
furnace to perform firing in air at 65.degree. C. for 12 hours.
[0060] With respect to the thus manufactured sample (CFRP substrate
1/intermediate layer 2/intermediate layer 3/top coating 4) is
conducted a test for a resistance to slurry erosion with an erosion
testing machine (WT-103)(made by Mako Co., Ltd.) several times. A
grinding material is WA#600 (average particle size: about 25 .mu.m)
and has a concentration of 5 wt %, and a projection distance is 10
mm (at a projection angle of 90.degree.), and a projection angle is
60.degree., and an air pressure is 0.3 MPa, and a testing time is
1, 2, 3 and 5 minutes.
[0061] Also, the same test is conducted to CFRP substrate not
subjected to a surface treatment (Comparative Example 1)
[0062] The test results are shown in FIG. 2. It can been seen that
the sample of Example 1 obtained by forming B.sub.4C thermal
sprayed coating on the CFRP substrate is small in the Py value
(scattering index of coating thickness) and excellent in the
resistance to slurry erosion as compared to a sample of CFRP
substrate not subjected to the surface treatment as Comparative
Example 1.
[0063] From the above is recognized an effect of improving surface
properties to the carbon fiber-reinforced plastic substrate.
Example 2
[0064] This example reports results evaluated on the resistance to
blast erosion, adhesiveness and hardness of a structure obtained by
forming B.sub.4C thermal sprayed coating on a carbon
fiber-reinforced plastic (CFRP) substrate.
[0065] (Preparation of Samples)
[0066] Sample 1
[0067] There is first provided CFRP substrate of 50 mm.times.50 mm
having a thickness of 3 mm using an epoxy-based resin as a binder,
which is ground with a surface grinder for correcting the flatness
thereof.
[0068] Subsequently, a mixture of 40 vol % of an epoxy-based resin
and 60 vol % of zirconium oxide (ZrO.sub.2) particles (average
particle size: 35 .mu.m) is applied to a surface to be coated as a
coating having a thickness of 100 .mu.m with a compressed air
driving gun to form an underlying intermediate layer.
[0069] After the formation of the underlying intermediate layer, a
sample is inserted into an electric furnace and fired in air at
100.degree. C. for 4 hours.
[0070] Next, a mixture of 78 wt % of aluminum oxide
(Al.sub.2O.sub.3) and 22 wt % of silicon oxide (SiO.sub.2) is
sprayed onto a surface to be coated as a coating having a thickness
of 100 .mu.m with an atmospheric plasma spraying device to form an
upper intermediate layer.
[0071] Thereafter, B.sub.4C spraying material (average particle
size: 26 .mu.m) with a purity of 99% is applied by plasma spraying
as a coating having a thickness of 100 .mu.m in a controlled argon
atmosphere of 99.9%.
[0072] After the coating treatment, the same epoxy-based resin as
in the underlying intermediate layer is impregnated into the
B.sub.4C thermal sprayed coating as an outermost layer and inserted
into an electric furnace to conduct firing in air at 65.degree. C.
for 12 hours to thereby form a sample 1.
[0073] Sample 2
[0074] The substrate and intermediate layers are prepared in the
same manner as in Sample 1, and then B.sub.4C spraying material
(average particle size: 26 .mu.m) with a purity of 99% is
plasma-sprayed in air to form a coating having a thickness of 100
.mu.m as an outermost layer. After the coating treatment, the
impregnation treatment and firing treatment are conducted in the
same manner as in Sample 1 to form a sample 2.
[0075] Sample 3
[0076] The substrate and intermediate layers are prepared in the
same manner as in Sample 1, and then B.sub.4C spraying material
(average particle size: 26 .mu.m) with a purity of 95% is
plasma-sprayed in a controlled argon atmosphere of 99.9% to form a
coating having a thickness of 100 pun as an outermost layer. After
the coating treatment, the impregnation treatment and firing
treatment are conducted in the same manner as in Sample 1 to form a
sample 3.
[0077] Sample 4
[0078] There is provided the same substrate as in Sample 1.
Subsequently, a metallic Al is sprayed on a surface to be coated as
a coating having a thickness of 100 .mu.m with an atmospheric
plasma spraying device to form an intermediate layer.
[0079] Thereafter, B.sub.4C spraying material (average particle
size: 26 .mu.m) with a purity of 99% is plasma-sprayed in a
controlled argon atmosphere of 99.9% to form a coating having a
thickness of 100 .mu.m as an outermost layer. After the coating
treatment, the impregnation treatment and firing treatment are
conducted in the same manner as in Sample 1 to form a sample 4.
[0080] Sample 5
[0081] As a sample of CFRP substrate not subjected to a surface
treatment is provided CFRP substrate of 50 mm.times.50 mm having a
thickness of 3 mm using an epoxy-based resin as a binder, which is
ground with a surface grinder for correcting the flatness thereof
to form a sample 5.
[0082] The constructions of the aforementioned samples 1-5 are
shown in following Table 2.
TABLE-US-00002 TABLE 2 Intermediate layer (underlying layer/
Outermost Sample Substrate upper layer) layer Process 1 CFRP Epoxy
resin-ZrO.sub.2/ B.sub.4C Controlled Al.sub.2O.sub.3--SiO.sub.2
(purity: 99%) atmosphere thermal spraying 2 CFRP Epoxy
resin-ZrO.sub.2/ B.sub.4C Atmospheric Al.sub.2O.sub.3--SiO.sub.2
(purity: 99%) plasma spraying 3 CFRP Epoxy resin-ZrO.sub.2/
B.sub.4C Controlled Al.sub.2O.sub.3--SiO.sub.2 (purity: 95%)
atmosphere thermal spraying 4 CFRP Al B.sub.4C Controlled (purity:
99%) atmosphere thermal spraying 5 CFRP -- -- --
[0083] (Blast Erosion Test)
[0084] With respect to each of the samples 1-5 is conducted a blast
erosion test using an erosion testing machine. The grinding
material is silica sand No. 8 (particle size: 50-100 .mu.m), and a
nozzle diameter .phi. is 1.5 mm, and a projection distance is 15
mm, and a projection angle is 60.degree., and a feed amount of the
grinding material is 12 g/min, and an air flow rate is 6.0 L/min,
and a test time is 4 minutes.
[0085] The test results are shown in Table 3. It can be seen that
all of the samples 1-4 are considerably excellent in the resistance
to blast erosion as compared to the sample 5 not subjected to the
surface treatment.
[0086] (Adhesiveness Test)
[0087] The adhesion force of the thermal sprayed coating in each of
the samples 1-4 is measured by a test method for tensile adhesion
strength defined in JIS H8402. As an adhesive is used a two-pack
cold curing-type adhesive (Dev-Tube S-6 made by Illinois Tool Works
Corporation).
[0088] The test results are shown in Table 3. It can be seen that
all of the samples 1-4 have a satisfactory adhesion force (not less
than 10 MPa).
[0089] (Hardness Test)
[0090] With respect to each of the samples 1-4 is made a test for
micro-Vickers hardness. A measuring load is 100 gf, and an average
value is taken for 10 measuring points.
[0091] The test results are shown in Table 3. It can be seen that
all of the samples 1-4 have a satisfactory hardness.
TABLE-US-00003 TABLE 3 Abrasion volume by Adhesion Vickers Sample
blast erosion (.mu.m) force (MPa) hardness 1 24.5 13.6 1105 2 57.4
13.4 970 3 47.3 15.5 758 4 18.5 11.1 1137 5 132.8 -- --
Example 3
[0092] This example reports results evaluated on a resistance to
blast erosion every a substrate in structures formed by applying
B.sub.4C thermal sprayed coating onto fiber-reinforced plastic
substrates. The evaluation is performed on three kinds of CFRP
material (epoxy-based resin), CFRP material (bakelite) and
glass-epoxy material.
[0093] (Preparation of Samples)
[0094] Sample 6
[0095] As CFRP material (epoxy-based resin) is provided the same as
in Sample 1.
[0096] Sample 7
[0097] As CFRP material (bakelite) is provided CFRP substrate of 50
mm.times.50 mm having a thickness of 5 mm using bakelite as a
binder, which is ground with a surface grinder for correcting the
flatness thereof. Subsequently, an intermediate layer and an
outermost layer are formed according to the same manner as in
Sample 1.
[0098] Sample 8
[0099] As a glass-epoxy material is provided a glass
fiber-reinforced plastic substrate of 50 mm.times.50 mm having a
thickness of 5 mm using an epoxy-based resin as a binder, which is
ground with a surface grinder for correcting the flatness thereof.
Subsequently, an intermediate layer and an outermost layer are
formed according to the same manner as in Sample 1.
[0100] (Blast Erosion Test)
[0101] With respect to each of the samples 6-8 is conducted a blast
erosion test using an erosion testing machine. The grinding
material is WA #220 (average particle size: 67 .mu.m), and a nozzle
diameter 4) is 1.5 mm, and a projection distance is 15 mm, and a
projection angle is 60.degree., and a feed amount of the grinding
material is 20 g/min, and an air flow rate is 6.0 L/min, and a test
time is 3 minutes.
[0102] The test results are shown in Table 4. All of the samples
6-8 are substantially equal in the resistance to blast erosion.
TABLE-US-00004 TABLE 4 Abrasion volume Sample by blast erosion
(.mu.m) 6 163.8 7 197.5 8 200.5
INDUSTRIAL APPLICABILITY
[0103] As mentioned above, the fiber-reinforce resin structure
according to the invention can be applied to a fan blade of an
engine for airplanes, a turbine blade of a compressor for airplane
engine, members in a primary wing and a fuselage of an airplane and
a mold used for the manufacture thereof, a turbine blade for a
steam turbine, a roll for the manufacture of a paper film, a
pressure vessel, a transfer member for semiconductor wafers and FPD
substrates, automobile parts, solar buttery members and flames for
space equipment, members for wind power generation, inner tube for
a chimney, parts for Shinkansen bullet trains and rail vehicles,
and so on.
DESCRIPTION OF REFERENCE SYMBOLS
[0104] 1: substrate [0105] 2: intermediate layer (intermediate
layer A) [0106] 3: intermediate layer (intermediate layer B) [0107]
4: top coating [0108] 10: fiber-reinforced resin structure
* * * * *