U.S. patent application number 13/431159 was filed with the patent office on 2012-09-06 for amorphous alloy die cast and heat treatment process of the same.
Invention is credited to Yunchun LI, Faliang Zhang.
Application Number | 20120222785 13/431159 |
Document ID | / |
Family ID | 45529427 |
Filed Date | 2012-09-06 |
United States Patent
Application |
20120222785 |
Kind Code |
A1 |
LI; Yunchun ; et
al. |
September 6, 2012 |
AMORPHOUS ALLOY DIE CAST AND HEAT TREATMENT PROCESS OF THE SAME
Abstract
A heat treatment process for an amorphous alloy die cast
comprises: the amorphous alloy die cast is subjected to an aging
treatment at a temperature of about 0.5-0.6 Tg, for a time of about
10 minutes to about 24 hours. The amorphous alloy die cast
comprises Zr, and is represented by a formula of
(Zr.sub.1-xTi.sub.x).sub.a(Cu.sub.1-yNi.sub.y).sub.bAl.sub.cM.sub.d,
in which M is selected from the group consisting of: Be, Y, Sc, La,
and combinations thereof, 38.ltoreq.a.ltoreq.65,
0.ltoreq.x.ltoreq.0.45, 0.ltoreq.y.ltoreq.0.75,
20.ltoreq.b.ltoreq.40, 0.ltoreq.c.ltoreq.15, 0.ltoreq.d.ltoreq.30,
and the sum of a, b, c, and d in atomic percentages equals to
100.
Inventors: |
LI; Yunchun; (Shenzhen,
CN) ; Zhang; Faliang; (Shenzhen, CN) |
Family ID: |
45529427 |
Appl. No.: |
13/431159 |
Filed: |
March 27, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/CN2011/077762 |
Jul 28, 2011 |
|
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13431159 |
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Current U.S.
Class: |
148/561 ;
148/403 |
Current CPC
Class: |
C22C 1/002 20130101;
C22C 45/10 20130101; C22C 16/00 20130101; C22F 1/18 20130101; B22D
17/00 20130101 |
Class at
Publication: |
148/561 ;
148/403 |
International
Class: |
C22F 1/18 20060101
C22F001/18; C22C 45/10 20060101 C22C045/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 29, 2010 |
CN |
201010244468.7 |
Claims
1. A heat treatment process for an amorphous alloy die cast
comprising: subjecting the amorphous alloy die cast to an aging
treatment at a temperature of about 0.5 Tg to about 0.6 Tg, wherein
Tg is a glass transition temperature of the alloy, and for a time
period of about 10 minutes to about 24 hours.
2. The heat treatment process of claim 1, wherein the temperature
is about 0.53 Tg to about 0.57 Tg, and the time period is about 30
minutes to about 60 minutes.
3. The heat treatment process of claim 1, wherein the amorphous
alloy die cast is formed by a die casting process in a condition of
a pressure of about 50 Pa to about 200 Pa and a die casting speed
of about 3 m/s to about 5 m/s.
4. The heat treatment process of claim 1, wherein the amorphous
alloy die cast has a thickness of about 0.5 mm to about 2 mm.
5. The heat treatment process of claim 1, wherein the amorphous
alloy die cast has a thickness of about 1.0 mm to about 1.5 mm.
6. The heat treatment process of claim 1, wherein the aging
treatment is performed under a positive pressure of about 0.1 MPa
to about 0.5 MPa.
7. The heat treatment process of any one of claims 1, 3, 4, and 6,
wherein the amorphous alloy die cast comprises Zr, and is
represented by a formula of
(Zr.sub.1-xTi.sub.x).sub.a(Cu.sub.1-yNi.sub.y).sub.bAl.sub.cM.sub.d,
wherein M is selected from the group consisting of: Be, Y, Sc, La,
and combinations thereof, "x" is in the range of from 0 to 0.45 in
atomic percentage, "y" is in the range of from 0 to 0.75 in atomic
percentage, "a" is in the range of from 38 to 65, "b" is in the
range of from 20 to 40, "c" is in the range of from 0 to 15, "d" is
in the range of from 0 to 30, and the sum of a, b, c, and d in
atomic percentage equals to 100.
8. An amorphous alloy die cast, wherein the amorphous alloy die
cast comprises Zr and is treated by the heat treatment process
described in any one of claims 1, 3, 4, and 6.
9. The amorphous alloy die cast of claim 8, wherein the amorphous
alloy die cast is represented by a formula of
(Zr.sub.1-xTi.sub.x).sub.a(Cu.sub.1-yNi.sub.y).sub.bAl.sub.cM.sub.d,
in which M is selected from the group consisting of: Be, Y, Sc, La,
and combinations thereof, "x" is in the range of from 0 to 0.45,
"y" is in the range of from 0 to 0.75, "a" is in the range of from
38 to 65, "b" is in the range of from 20 to 40, "c" is in the range
of from 0 to 15, "d" is in the range of from 0 to 30, and the sum
of a, b, c, and d in atomic percentage equals to 100.
10. The amorphous alloy die cast of claim 9, wherein the amorphous
alloy die cast is represented by a formula of
Zr.sub.55Al.sub.15Cu.sub.25Ni.sub.5 or
Zr.sub.41Ti.sub.14Cu.sub.15Ni.sub.10Be.sub.20.
11. The amorphous alloy die cast of claim 8, wherein the amorphous
alloy die cast has a thickness of about 0.5 mm to about 2 mm.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of International
Patent Application No. PCT/CN2011/077762, filed Jul. 28, 2011,
entitled "AMORPHOUS ALLOY DIE CAST AND HEATING PROCESS OF THE
SAME", which claims the priority and benefit of Chinese Patent
Application No. 201010244468.7, filed with the State Intellectual
Property Office of the P. R. China on Jul. 29, 2010. The entire
content of both applications are incorporated herein by
reference.
FIELD OF THE PRESENT DISCLOSURE
[0002] The present disclosure relates to methods of manufacturing
amorphous alloys, more particularly to an amorphous alloy die cast
and a heat treatment process of the same.
BACKGROUND
[0003] Extensive research and numerous experiments demonstrated
that crystal boundaries, dislocations, stacking faults, or other
crystal defects do not exist in amorphous alloys. Hence, amorphous
alloys possess a plurality of advantageous material properties that
crystal metals do not have, such as better corrosion resistance,
higher frictional resistance, and improved magnetic and electric
properties. Amorphous alloys are widely used in electronic,
mechanical, chemical, and national defense industries.
[0004] At present, bulk amorphous alloy, also known as metallic
glass, is usually formed by rapid cooling of melted metal alloy to
a temperature below the glass transition temperature. It is
believed that rapid cooling may prevent the formation and growth of
crystal nucleus. Thus the melted alloy may solidify directly to
form amorphous alloy which has a long range disordered structure.
Bulk amorphous alloys usually are millimeter-sized. Nowadays, bulk
amorphous alloys are mainly prepared in research laboratories.
Amorphous alloys may be prepared by several processes including
melting and suction-casting process in an electrical arc furnace,
solvent packaging process, water quenching process, or other
processes. However, in these processes, preparation of bulk
amorphous alloys to achieve desired material properties may require
stringent processing conditions, such as highly purified raw
materials, high degree of vacuum, very rapid cooling, etc. These
processes may not be applicable in the manufacturing industry
because of their high costs and low efficiencies.
[0005] Therefore, large corporations and research institutes are
both seeking for an amorphous alloy preparation process suitable
for high volume manufacturing under normal processing conditions.
Die casting is one of the most popular methods for preparing
amorphous alloys. However, material properties are usually unstable
for amorphous alloys prepared by present die castings processing
method under current available conditions. Thus, the applications
of amorphous alloys obtained by die casting are very limited.
[0006] Chinese Patent Application Publication No. CN101550521A
discloses a rare-earth-based bulk amorphous alloy and its composite
material. The composite material is obtained based on the bulk
amorphous alloy through a heat treatment process. The heat
treatment process includes an isothermal annealing of the
rare-earth-based bulk amorphous alloy in a furnace at a temperature
within the supercooled liquid region (325-650.degree. C.). The
process is performed in a 10.sup.-3 Pa vacuum environment. The
composite material prepared thereof has improved thermal stability,
higher electrical resistance, good soft magnetic property, and
excellent processing capability in the supercooled liquid region.
However, this heat treatment process requires relatively high
annealing temperature. The temperature required must reside in the
supercooled liquid region and is higher than the glass transition
temperature Tg. Hence, the annealing process may cause portion of
the amorphous alloy become crystallized.
SUMMARY
[0007] The present disclosure aims to solve at least one of the
foregoing problems, including the unstable properties of amorphous
alloy obtained by die-casting techniques and complexity associated
with known processes of bulk amorphous alloy preparation.
[0008] One embodiment of the present disclosure provides a novel
heat treatment process of an amorphous alloy die cast. The heat
treatment process includes an aging treatment performed to the
amorphous alloy die cast at a temperature of about 0.5 Tg to about
0.6 Tg for a time period of about 10 minutes to about 24 hours.
[0009] In one embodiment, the amorphous alloy die cast may be
prepared by a low-speed die casting process in a vacuum
environment. The process is performed under a pressure of about 50
Pascal (Pa) to about 200 Pa, with a die casting speed of about 3
meter per second (m/s) to about 5 m/s. The amorphous alloy die cast
may have a thickness of about 0.5 millimeter (mm) to about 2
mm.
[0010] In some embodiments, the aging process may be performed in a
positive pressure of about 0.1 MPa to about 0.5 MPa.
[0011] In some embodiments, the amorphous alloy die cast may have a
thickness of about 1.0 mm to about 1.5 mm. The aging treatment may
be performed at a temperature of about 0.53 Tg to about 0.57 Tg,
for a time period of about 30 minutes to about 60 minutes.
[0012] In another embodiment of the present disclosure, a Zirconium
(element Zr) based amorphous alloy die cast is provided. The
Zirconium based amorphous alloy die cast may be prepared by the
heat treatment processes described above. The Zirconium based
amorphous alloy die cast may be composed of
(Zr.sub.1-xTi.sub.x).sub.a(Cu.sub.1-yNi.sub.y).sub.bAl.sub.cM.sub.d,
wherein M may be selected from the group consisting of Be, Y, Sc,
La, and combinations thereof; and 38.ltoreq.a.ltoreq.65,
0.ltoreq.x.ltoreq.0.45, 0.ltoreq.y.ltoreq.0.75,
20.ltoreq.b.ltoreq.40, 0.ltoreq.c.ltoreq.15, 0.ltoreq.d.ltoreq.30;
and the sum of a, b, c, and d in atomic percentages equals to
100.
[0013] In various embodiments, the amorphous alloy die cast
obtained by the disclosed heat treatment process exhibits higher
bending resistance and decreased property instability.
[0014] While the amorphous alloys and methods thereof will be
described in connection with various preferred illustrative
embodiments, it will be understood that it is not intended to limit
the amorphous alloy die casts and methods thereof to those
embodiments. On the contrary, it is intended to cover all
alternatives, modifications, and equivalents as may be included
within the spirit and scope of the disclosed subject matter as
defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] These and other aspects and advantages of the present
disclosure will become apparent and more readily appreciated from
the following descriptions taken in conjunction with the drawings,
in which:
[0016] FIG. 1 shows the X-ray Diffraction (XRD) patterns of samples
A1, B1, and C1 according to an embodiment of the present
disclosure; and
[0017] FIG. 2 shows the Differential Scanning calorimetry (DSC)
patterns of samples A1, B1, and C1 according to an embodiment of
the present disclosure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0018] Traditional amorphous alloy die cast is usually not
subjected to heat treatment. During the high-pressure, high-speed
casting process of traditional metal alloys such as Aluminum
alloys, Zinc alloys, or Magnesium alloys, gas in the die cast mold
can be unavoidably trapped inside the die cast and form subsurface
porosities. If the die cast is subsequently subjected to a heat
treatment process, gas bubbles may be formed at the surface,
causing deformation of the die cast. Hence, both the properties and
the appearance of the die cast are negatively affected.
[0019] In contrast to traditional Aluminum, Zinc, Magnesium or
their combinational alloys, amorphous alloy has a low temperature
supercooled liquid region. The disclosed subject matter provides a
novel process method that utilizes this supercooled liquid region
to significantly reduce the gas trapped in the amorphous alloy
comparing to that in the traditional metal alloys. Specifically,
the disclosed subject matter provides a die casting process that is
performed under a vacuum pressure of about 50 Pa to about 200 Pa,
and at a low die casting speed of about 3 m/s to about 5 m/s. In
addition, risk of die cast bubbling during heat treatment may be
effectively eliminated if the post die cast heat treatment is
performed under atmospheric pressure or positive pressure, i.e.,
about 0.1 Pa to about 0.5 MPa, in the range of middle to high
pressure.
[0020] One embodiment of the present disclosure discloses a novel
heat treatment process of an amorphous alloy die cast. The heat
treatment process comprises two steps.
[0021] The first step comprises die casting and molding the
amorphous alloy die cast at a pressure of about 50 Pa to about 200
Pa and at a die casting speed of about 3 m/s to about 5 m/s. The
resulted amorphous alloy die cast may have a thickness ranging from
about 0.5 mm to about 2 mm, with most of the die casts having
thicknesses ranging from about 1.0 mm to about 1.5 mm.
[0022] The second step comprises performing an aging treatment on
the amorphous alloy die cast, at a temperature of about 0.5 Tg to
about 0.6 Tg, for a time period of about 10 minutes to about 24
hours. Tg refers to the glass transition temperature measured in
Kelvin. A particular Tg of a certain amorphous alloy may be
obtained by DSC testing. DSC testing is a currently known
technique. The aging treatment may be performed at atmospheric
pressure or positive pressure. In some embodiments, a positive
pressure of about 0.1 MPa to about 0.5 MPa is preferred in order to
prohibit gas from diffusing to the surface of the die cast. In some
embodiments, the preferred aging temperature is about 0.53 Tg to
about 0.57 Tg and the preferred aging time period is about 30
minutes to about 60 minutes for a amorphous alloy die cast with a
thickness of about 1.0 mm to about 1.5 mm. Corresponding to
different thicknesses of the die cast, the preferred aging
treatment temperature may be increased or decreased; and the
preferred heat treatment time period may be shortened or extended.
However, the aging treatment should be kept within about 0.5 Tg to
about 0.6 Tg range.
[0023] In various embodiments of the present disclosure, the
amorphous alloy die cast that is subjected to the above disclosed
heat treatment process neither crystallizes, nor has gas bubbles at
the surface. The die cast exhibits improved material properties and
enhanced stability. These improvements may be attributed to the
following reasons.
[0024] First, during the amorphous alloy die cast preparation
process, the die cast is cooled off after molding. Cooling rates at
different parts of the die cast are different. The different
cooling rates may cause some weak areas or stress concentration
regions. In the present disclosure, the low aging treatment
temperature ranging from about 0.5 Tg to about 0.6 Tg enables the
relaxation and releasing of the concentrated stresses. Hence, the
process disclosed in the present disclosure prevents the amorphous
alloy die cast from premature fracturing before the material's
yield point is reached. As a result, the material's performance and
stability of the die cast are improved.
[0025] Second, the amorphous alloy die cast is formed at a vacuum
pressure of about 50 Pa to about 200 Pa and at a low casting speed
of about 3 m/s to about 5 m/s. Because the amorphous alloy has a
high viscosity, the amount of gases trapped within the amorphous
alloy die cast is less than that in the traditional alloy die
casts. During subsequent aging treatment performed under middle to
high pressure (about 0.1 MPa to about 0.5 MPa), the positive
pressure prohibits the trapped gas from diffusing to the surface of
the amorphous alloy die cast.
[0026] Third, when amorphous alloy is rapidly cooled, the
microstructure of the amorphous alloy is in a highly disordered and
unstable state. While the low temperature aging treatment may not
provide sufficient energy to overcome the energy barrier required
for crystallization, it can overcome the metastable energy barrier
and enable the transformation of the material structure from a
high-energy long-range disordered state to a short-range ordered
state. Here, the low temperature aging refers to aging treatment
performed below the glass transition temperature. The current
disclosure discloses that such a temperature range is from about
0.5 Tg to about 0.6 Tg.
[0027] After the low temperature aging process, the alloy may
become, for example, pentagonal or dodecagonal quasicrystals, both
have short-range ordered structures. Although the short-range
ordered structure cannot grow to become crystal, (the
crystallization process requires re-melting into a disordered
state), it can enhance the stability of the material properties.
Referring to FIG. 2, after the aging treatment, the die cast
exhibits an increased area under the crystallization peak. The
increased area under the crystallization peak indicates more energy
is released during the crystallization and in turn, indicates a
more stable crystal structure and a more stable material
property.
[0028] Reference will be made in detail to embodiments of the
present disclosure. The embodiments described herein with reference
to drawings are explanatory, illustrative, and used to generally
understand the present disclosure. The embodiments shall not be
construed to limit the present disclosure. The same or similar
elements and the elements having same or similar functions are
denoted by like reference numerals throughout the descriptions.
[0029] In the two embodiments disclosed, aging treatments were
performed on two typical Zr-based amorphous alloys composed of
Zr.sub.55Al.sub.15Cu.sub.25Ni.sub.5 and
Zr.sub.41Ti.sub.14Cu.sub.15Ni.sub.10Be.sub.20, respectively. The
two amorphous alloys have excellent glass forming ability,
excellent mechanical properties and broad supercooled liquid
region. Therefore, these two typical Zr-based alloys are selected
to explain the effects of the aging treatment on the amorphous
alloys.
[0030] In the first embodiment, high purity (purity is greater than
99.0 wt %) Zr, Al, Cu, and Ni with a weight ratio corresponding to
the composition of Zr.sub.55Al.sub.15Cu.sub.25Ni.sub.5 were melted
in an electrical arc furnace. Subsequently, a copper mould was used
for die casting in the presence of a protective Argon gas. The die
casting was performed in a condition of a pressure of 150 Pa and a
casting speed of 3m/s. Fifteen amorphous alloy die casts were
prepared for experimental purposes, each having a size of 80
mm.times.6 mm.times.1.5 mm. The fifteen amorphous alloy die casts
were labeled as A1 to A15, and having a composition of
Zr.sub.55Al.sub.15Cu.sub.25Ni.sub.5. The glass transition
temperature Tg was determined to be 704K for this type of alloy by
performing a DSC test. The fifteen die casts were divided into
three groups.
[0031] The first group includes A1 to A5, all of which were not
subjected to any aging treatments.
[0032] The second group includes A6 to A10, each of which was
subjected to an aging treatment in a pressure of 0.2 MPa, at a
temperature of 0.53 Tg (373K) , for a time period of 1 hour. The
resulted die casts were labeled as B1 to B5.
[0033] The third group includes A11 to A15, each of which was
subjected to an aging treatment in a pressure of 0.2 MPa, at a
temperature of 0.81 Tg (573K) , for a time period of 1 hour. The
resulted die casts were labeled as C1 to C5.
[0034] Property Tests
[0035] 1) Bending Resistance Test
[0036] Pursuing to standard bending resistance test disclosed in
GB/T14452-93 and using a CMT5105 universal material testing
machine, the three-point bending fracturing tests were performed on
each of the die casts groups A1-A5, B1-B5, and C1-C5. The resulted
strength values were recorded. The average and variance of the
strength values were calculated. All data are shown in Table 1.
[0037] 2) XRD (X-Ray Diffraction) Analysis
[0038] In order to determine whether the alloy is amorphous, X-ray
powder diffraction analyses were performed on die cast samples A1,
B1, and C1. A D-MAX2200PC X-ray powder diffraction instrument was
used, and the XRD analyses were performed under the following
conditions: X-ray radiation was generated by a copper target; the
incident wavelength X is 1.54060A; the accelerating voltage is 40
KV; the current is 20 mA; and the scan step is 0.04.degree. . The
XRD results are shown in FIG. 1. It can be seen that A1 and B1 have
amorphous structures and C1 has a crystal structure (the sharp
diffraction peaks of C1 indicate a crystal structure).
[0039] 3) DSC Test
[0040] DSC tests were performed on A1, B1, and C1 with a STA409
Thermogravimetric and Differential Thermal Analyzer. An 99% pure
Al.sub.2O.sub.3 crucible was selected. The results are shown in
FIG. 2. It can be seen that Bl, which was subjected to an aging
treatment at a temperature of 0.53 Tg, exhibits an increased area
under the crystal peaks. The increased area means a more stable
material property.
TABLE-US-00001 TABLE 1 Bending Bending Bending Strength Strength
Strength Group 1 (MPa) Group 2 (MPa) Group 3 (MPa) A1 1978.15 B1
2695.73 C1 965.02 A2 1645.26 B2 2681.6 C2 644.58 A3 1768.73 B3
2282.61 C3 1248.12 A4 1471.5 B4 2362.84 C4 683.6 A5 2280.92 B5
2482.1 C5 621.37 Average 1828.912 Average 2500.976 Average 832.538
Variance 333.7656 Variance 150.1512 Variance 219.2256
[0041] In the second embodiment, high purity (purity is greater
than 99.0wt %) Zr, Ti, Cu, Ni and Be with a weight ratio
corresponding to the composition of
Zr.sub.41Ti.sub.14Cu.sub.15Ni.sub.10Be.sub.20 were melted in an
electrical arc furnace. Subsequently, a copper mould was used for
die casting in the presence of a protective Argon gas. The die
casting was performed under a pressure of 120 Pa and with a casting
speed of 4 m/s. Fifteen amorphous alloy die casts were prepared for
experimental purposes, each having a size of 80 mm.times.18
mm.times.1 mm. The fifteen amorphous alloy die casts were
transition temperature Tg was determined to be 662K for this type
of alloy by performing a DSC test. The fifteen die casts were
divided into three groups.
[0042] The first group includes D1 to D5, all of which were not
subjected to any aging treatments.
[0043] The second group includes D6 to D10, each of which was
subjected to an aging treatment in an atmospheric pressure of 0.1
MPa, at a temperature of 0.57 Tg (377K) , for a time period of 0.5
hour. The resulted die casts were labeled as E1 to E5.
[0044] The third group includes D11 to D15, each of which was
subjected to an aging treatment under a pressure of 0.1 MPa, at a
temperature of 0.47 Tg (311 K) , for a time period of 0.5 hour. The
resulted die casts were labeled as F1 to F5.
[0045] Property Test
[0046] Bending resistance strength test was performed on the 3
groups of die casts.
[0047] Pursuing to standard bending resistance test disclosed in
GB/T14452-93 and using a CMT5105 universal material testing
machine, the three-point bending fracturing tests were performed on
each of the die casts groups D1-D5, E1-E5, and F1-F5. The resulted
strength values were recorded. The average and variance of the
strength values were calculated. All data are shown in Table 2.
TABLE-US-00002 TABLE 2 Bending Bending Bending Strength Strength
Strength Group 1 (MPa) Group 2 (MPa) Group 3 (MPa) D1 2077.9 E1
2321.8 F1 2184.69 D2 1937.27 E2 2423.4 F2 2023.29 D3 1606.07 E3
2845.43 F3 1721.34 D4 1715.41 E4 2343.16 F4 1763.76 D5 1660.24 E5
2275.54 F5 2107.59 Average 1799.378 Average 2441.866 Average
1960.134 Variance 338.1664 Variance 161.4256 Variance 300.6715
[0048] Conclusion of the Experiments
[0049] Referring to Table 1, it is shown that die casts B1-B5,
which were subjected to an aging treatment at a temperature of 0.53
Tg, have better bending resistance and stability in comparison with
die casts A1-A5, which were not subjected to aging treatments, and
C1-C5, which subjected to an aging treatment at a temperature of
0.81 Tg. Referring to Table 2, die casts E1-E5 have improved
bending resistance and stability, in comparison with die casts
D1-D5, which were not subjected to any aging treatments, and die
casts F1-F5, which were subjected to aging treatments under a
temperature of 0.47 Tg.
[0050] In this specification, the terms "one embodiment," "some
embodiments," "exemplary embodiment," "specific exemplary
embodiment," or "some exemplary embodiments" mean that the
described specific characteristics, structures, materials or
features based on the underlining embodiments exist in at least one
of the embodiments or exemplary embodiments. However, in this
specification, an exemplary description associated with the above
terms does not necessarily mean the same embodiment. In addition,
the described specific characteristics, structures, materials or
features may be properly combined in one or more embodiments or
exemplary embodiments.
[0051] Although explanatory embodiments have been shown and
described, it would be appreciated by those skilled in the art that
changes, alternatives, and modifications all falling into the scope
of the claims and their equivalents may be made in the embodiments
without departing from spirit and principles of the present
disclosure.
* * * * *