U.S. patent application number 09/187656 was filed with the patent office on 2002-06-20 for bulk amorphous metal magnetic components for electric motors.
Invention is credited to DECRISTOFARO, NICHOLAS JOHN, STAMATIS, PETER JOSEPH.
Application Number | 20020074885 09/187656 |
Document ID | / |
Family ID | 22689904 |
Filed Date | 2002-06-20 |
United States Patent
Application |
20020074885 |
Kind Code |
A1 |
DECRISTOFARO, NICHOLAS JOHN ;
et al. |
June 20, 2002 |
BULK AMORPHOUS METAL MAGNETIC COMPONENTS FOR ELECTRIC MOTORS
Abstract
A high efficiency electric motor has a generally polyhedrally
shaped bulk amorphous metal magnetic component in which a plurality
of layers of amorphous metal strips are laminated together to form
a generally three-dimensional part having the shape of a
polyhedron. The bulk amorphous metal magnetic component may include
an arcuate surface, and preferably includes two arcuate surfaces
that are disposed opposite to each other. The magnetic component is
operable at frequencies ranging from between approximately 60 Hz
and 20,000 Hz and exhibits (i) a core-loss of less than or
approximately equal to 1 watt-per-kilogram of amorphous metal
material when operated at a frequency of approximately 60 Hz and at
a flux density of approximately 1.4 Tesla (T); (ii) a core-loss of
less than or approximately equal to 20 watts-per-kilogram of
amorphous metal material when operated at a frequency of
approximately 1000 Hz and at a flux density of approximately 1.4 T
and (iii) a core-loss of less than or approximately equal to 70
watt-per-kilogram of amorphous metal material when operated at a
frequency of approximately 20,000 Hz and at a flux density of
approximately 0.30T. Performance characteristics of the bulk
amorphous metal magnetic component of the present invention are
significantly better when compared to silicon-steel components
operated over the same frequency range.
Inventors: |
DECRISTOFARO, NICHOLAS JOHN;
(CHATHAM, NJ) ; STAMATIS, PETER JOSEPH;
(MORRISTOWN, NJ) |
Correspondence
Address: |
HONEYWELL INTERNATIONAL INC
ATTN: ROGER H. CRISS
101 COLUMBIA ROAD
MORRISTOWN
NJ
07962
US
|
Family ID: |
22689904 |
Appl. No.: |
09/187656 |
Filed: |
November 6, 1998 |
Current U.S.
Class: |
310/152 |
Current CPC
Class: |
H02K 1/02 20130101; H01F
1/15333 20130101; H02K 1/06 20130101 |
Class at
Publication: |
310/152 |
International
Class: |
H02K 021/00 |
Claims
What is claimed is:
1. An electric motor having at least one bulk amorphous metal
magnetic component comprising a plurality of substantially
similarly shaped layers of amorphous metal strips laminated
together to form a polyhedrally shaped part.
2. An electric motor as recited by claim 1, wherein each of said
amorphous metal strips having a composition defined essentially by
the formula: M.sub.70-85 Y.sub.5-20 Z.sub.0-20, subscripts in atom
percent, where "M" is at least one of Fe, Ni and Co, "Y" is at
least one of B, C and P, and "Z" is at least one of Si, Al and Ge;
with the provisos that (i) up to 10 atom percent of component "M"
can be replaced with at least one of the metallic species Ti, V,
Cr, Mn, Cu, Zr, Nb, Mo, Ta and W, and (ii) up to 10 atom percent of
components (Y+Z) can be replaced by at least one of the
non-metallic species In, Sn, Sb and Pb.
3. An electric motor as recited by claim 2, wherein each of said
strips has a composition defined essentially by the formula
Fe.sub.80B.sub.11Si.sub.9.
4. An electric motor as recited by claim 2, wherein said bulk
amorphous metal magnetic component comprises a part of a stator of
said electric motor.
5. An electric motor as recited by claim 2, wherein said bulk
amorphous metal magnetic component comprises a stator of said
electric motor.
6. An electric motor as recited by claim 2, wherein said bulk
amorphous metal magnetic component comprises a part of a rotor of
said electric motor.
7. An electric motor as recited by claim 2, wherein said bulk
amorphous metal magnetic component comprises a rotor of said
electric motor.
8. An electric motor as recited by claim 2, wherein said amorphous
metal magnetic component comprises a rotor and a stator of said
electric motor.
9. An electric motor as recited by claim 1, wherein said bulk
amorphous metal magnetic component a core-loss of less than or
approximately equal to 1 watt-per-kilogram of amorphous metal
material when operated at a frequency of approximately 60 Hz and a
flux density of approximately 1.4T.
10. An electric motor as recited by claim 1, wherein said bulk
amorphous metal magnetic component a core-loss of less than or
approximately equal to 20 watts-per-kilogram of amorphous metal
material when operated at a frequency of approximately 1000 Hz and
a flux density of approximately 1.4T.
11. An electric motor as recited by claim 1, wherein said bulk
amorphous metal magnetic component a core-loss of less than or
approximately equal to 70 watts-per-kilogram of amorphous metal
material when operated at a frequency of approximately 20,000 Hz
and a flux density of approximately 0.30T.
12. In an electric motor, at least one bulk amorphous metal
magnetic component comprising a plurality of substantially
similarly shaped layers of amorphous metal strips laminated
together to form a polyhedrally shaped part.
13. An electric motor as recited by claim 12, wherein said magnetic
component is a stator.
15. An electric motor as recited by claim 12, wherein said magnetic
component is a rotor.
16. An electric motor as recited by claim 12, wherein said motor
comprises a member selected from the group consisting of squirrel
cage motors, reluctance synchronous motors and switched reluctance
motors.
17. An electric motor as recited by claim 13, wherein said motor
comprises a member selected from the group consisting of variable
reluctance motors, eddy current motors, squirrel cage motors,
reluctance synchronous motors and switched reluctance motors.
18. An electric motor as recited by claim 14, wherein said motor
comprises a member selected from the group consisting of squirrel
cage motors, reluctance synchronous motors and switched reluctance
motors.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field Of The Invention
[0002] This invention relates to amorphous metal magnetic
components, and more particularly, to a high efficiency electric
motor having a generally polyhedrally shaped bulk amorphous metal
magnetic component.
[0003] 2. Description Of The Prior Art
[0004] An electric motor typically contains magnetic components
made from a plurality of stacked laminations of non-oriented
electrical steel. In variable reluctance motors and eddy current
motors, the stators are made from stacked laminations. Both the
stator and the rotor are made from stacked laminations in squirrel
cage motors, reluctance synchronous motors and switched reluctance
motors. Each lamination is typically formed by stamping, punching
or cutting the mechanically soft, non-oriented electrical steel
into the desired shape. The formal laminations are then stacked and
bound to form the rotor or stator.
[0005] Although amorphous metals offer superior magnetic
performance when compared to non-oriented electrical steels, they
have long been considered unsuitable for use in bulk magnetic
components such as the rotors and stators of electric motors due to
certain physical properties and the corresponding fabricating
limitations. For example, amorphous metals are thinner and harder
than non-oriented steel and consequently cause fabrication tools
and dies to wear more rapidly. The resulting increase in the
tooling and manufacturing costs makes fabricating bulk amorphous
metal magnetic components using such techniques commercially
impractical. The thinness of amorphous metals also translates into
an increased number of laminations in the assembled components,
further increasing the total cost of an amorphous metal rotor or
stator magnet assembly.
[0006] Amorphous metal is typically supplied in a thin continuous
ribbon having a uniform ribbon width. However, amorphous metal is a
very hard material, making it very difficult to cut or form easily,
and once annealed to achieve peak magnetic properties, becomes very
brittle. This makes it difficult and expensive to use conventional
approaches to construct a bulk amorphous metal magnetic component.
The brittleness of amorphous metal may also cause concern for the
durability of the bulk magnetic component in an application such as
an electric motor.
[0007] Another problem with bulk amorphous metal magnetic
components is that the magnetic permeability of amorphous metal
material is reduced when it is subjected to physical stresses. This
reduced permeability may be considerable depending upon the
intensity of the stresses on the amorphous metal material. As a
bulk amorphous metal magnetic component is subjected to stresses,
the efficiency at which the core directs or focuses magnetic flux
is reduced resulting in higher magnetic losses, increased heat
production, and reduced power. This stress sensitivity, due to the
magnetostrictive nature of the amorphous metal, may be caused by
stresses resulting from magnetic and mechanical forces during the
operation of the electric motor, mechanical stresses resulting from
mechanical clamping or otherwise fixing the bulk amorphous metal
magnetic components in place, or internal stresses caused by the
thermal expansion and/or expansion due to magnetic saturation of
the amorphous metal material.
SUMMARY OF THE INVENTION
[0008] The present invention provides a bulk amorphous metal
magnetic component having the shape of a polyhedron and being
comprised of a plurality of layers of amorphous metal strips for
use in highly efficient electric motors. Also provided by the
present invention is a method for making a bulk amorphous metal
magnetic component. The magnetic component is operable at
frequencies ranging from about 60 Hz to 20,000 Hz and exhibits
improved performance characteristics when compared to silicon-steel
magnetic components operated over the same frequency range. More
specifically, a magnetic component constructed in accordance with
the present invention will have (i) a core-loss of less than or
approximately equal to 1 watt-per-kilogram of amorphous metal
material when operated at a frequency of approximately 60 Hz and at
a flux density of approximately 1.4 Tesla (T); (ii) a core-loss of
less than or approximately equal to 20 watts-per-kilogram of
amorphous metal material when operated at a frequency of
approximately 1000 Hz and at a flux density of approximately 1.4 T,
and (iii) a core-loss of less than or approximately equal to 70
watt-per-kilogram of amorphous metal material when operated at a
frequency of approximately 20,000 Hz and at a flux density of
approximately 0.30T.
[0009] In a first embodiment of the present invention, a bulk
amorphous metal magnetic component comprises a plurality of
substantially similarly shaped layers of amorphous metal strips
laminated together to form a polyhedrally shaped part.
[0010] The present invention also provides a method of constructing
a bulk amorphous metal magnetic component. In accordance with a
first embodiment of the inventive method, amorphous metal strip
material is cut to form a plurality of cut strips having a
predetermined length. The cut strips are stacked to form a bar of
stacked amorphous metal strip material and annealed. The annealed,
stacked bar is impregnated with an epoxy resin and cured. The
stacked bar is then cut at predetermined lengths to provide a
plurality of polyhedrally shaped magnetic components having a
predetermined three-dimensional geometry. The preferred amorphous
metal material has a composition defined essentially by the formula
Fe.sub.80B.sub.11Si.sub.9.
[0011] In accordance with a second embodiment of the method of the
present invention, an amorphous metal ribbon is wound about a
mandrel to form a generally rectangular core having generally
radiused corners. The generally rectangular core is then annealed,
impregnated with epoxy resin and cured. The short sides of the
rectangular core are then cut to form two magnetic components
having a predetermined three-dimensional geometry that is the
approximate size and shape of said short sides of said generally
rectangular core. The radiused corners are removed from the long
sides of said generally rectangular core and the long sides of said
generally rectangular core are cut to form a plurality of
polyhedrally shaped magnetic components having the predetermined
three-dimensional geometry. The preferred amorphous metal material
has a composition defined essentially by the formula
Fe.sub.80B.sub.11Si.sub.9.
[0012] The present invention is also directed to a bulk amorphous
metal component constructed in accordance with the above-described
methods.
[0013] Construction of bulk amorphous metal magnetic components in
accordance with the present invention is especially suited for
amorphous metal stators or stator components in highly efficient,
variable reluctance motors and eddy current motors. Similarly, bulk
amorphous metal components may be used as both the rotor and the
stator in squirrel cage motors, reluctance synchronous motors and
switched reluctance motors. The advantages recognized by the
present invention include simplified manufacturing and reduced
manufacturing time, reduced stresses (i.e., magnetostrictive)
encountered during construction of bulk amorphous metal components,
and optimized performance of the finished amorphous metal magnetic
component.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will be more fully understood and further
advantages will become apparent when reference is had to the
following detailed description of the preferred embodiments of the
invention and the accompanying drawings, wherein like reference
numeral denote similar elements throughout the several views and in
which:
[0015] FIG. 1 is a perspective view of a bulk amorphous metal
magnetic component in the shape of a three-dimensional rectangle
constructed in accordance with the present invention;
[0016] FIG. 2A is a perspective view of a bulk amorphous metal
magnetic component having the shape of a prism and constructed in
accordance with the present invention;
[0017] FIG. 2B is a perspective view of a bulk amorphous metal
magnetic component having oppositely disposed arcuate surfaces and
constructed in accordance with the present invention;
[0018] FIG. 2C is a top view of a stator for an electric motor
constructed from six prism-shaped components as depicted in FIG. 2A
and six arcuate components as depicted in FIG. 2B;
[0019] FIG. 3A is a perspective view of a bulk amorphous metal
magnetic stator for an electric motor constructed in accordance
with the present invention;
[0020] FIG. 3B is a perspective view of a bulk amorphous metal
magnetic rotor for an electric motors constructed in accordance
with the present invention;
[0021] FIG. 3C is a top view of the stator and rotor for an
electric motor constructed from the stator of FIG. 3A and the rotor
of FIG. 3B;
[0022] FIG. 4 is a side view of a coil of amorphous metal strip
positioned to be cut and stacked in accordance with the present
invention;
[0023] FIG. 5 is a perspective view of a bar of amorphous metal
strips showing the cut lines to produce a plurality of generally
prism-shaped magnetic components in accordance with the present
invention;
[0024] FIG. 6 is a side view of a coil of amorphous metal strip
which is being wound about a mandrel to form a generally
rectangular core in accordance with the present invention; and
[0025] FIG. 7 is a perspective view of a generally rectangular
amorphous metal core showing the cut lines to produce a plurality
of generally prism-shaped magnetic components formed in accordance
with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] The present invention is directed to high efficiency motors
constructed using bulk amorphous metal components such as, for
example stators, rotors, and component parts for stators and
rotors. Generally polyhedrally shaped bulk amorphous metal
components are constructed in accordance with the present invention
having various geometries including, but not limited to,
rectangular, square, prism. In addition, any of the previously
mentioned geometric shapes may include at least one arcuate
surface, and preferably two oppositely disposed arcuate surfaces to
form a generally curved or arcuate bulk amorphous metal component.
Furthermore, complete stators and rotors may be constructed as a
bulk amorphous metal component in accordance with the present
invention. Those stators and rotors may have either a unitary
construction or they may be formed from a plurality of pieces which
collectively form the completed component. Alternatively, a stator
and/or rotor may be a composite structure comprised entirely of
amorphous metal parts or a combination of amorphous metal parts
with other magnetic materials.
[0027] Referring now to the drawings in detail, FIG. 1 depicts a
generally polyhedrally shaped bulk amorphous metal component 10. As
used herein, the term polyhedron refers to a multi-faced or sided
solid. This includes, but is not limited to, three-dimensional
rectangles, squares, trapezoids, and prisms. In addition, any of
the previously mentioned geometric shapes may include at least one,
and preferably two, arcuate surfaces or sides that are disposed
opposite each other to form a generally arcuately shaped component.
The magnetic component 10 depicted in FIG. 1 is comprised of a
plurality of substantially similarly shaped layers of amorphous
metal strip material 20 that are laminated together and annealed.
In a preferred embodiment, a three-dimensional magnetic component
10 constructed in accordance with the present invention and having
a flux density of approximately 1.4 Tesla (T) will have (i) a
core-loss of less than or approximately equal to 1
watt-per-kilogram of amorphous metal material when operated at a
frequency of approximately 60 Hz and at a flux density of
approximately 1.4 Tesla (T); (ii) a core-loss of less than or
approximately equal to 20 watts-per-kilogram of amorphous metal
material when operated at a frequency of approximately 1000 Hz and
at a flux density of approximately 1.4 T, and (iii) a core-loss of
less than or approximately equal to 70 watt-per-kilogram of
amorphous metal material when operated at a frequency of
approximately 20,000 Hz and at a flux density of approximately
0.30T. These performance values apply to the various embodiments of
the present invention, regardless of the specific geometry of the
bulk amorphous metal component.
[0028] The magnetic component 100 depicted in FIG. 2A is generally
prism-shaped and preferably includes five (5) sides 110 or
surfaces. The pentagonnally-shaped polyhedron component 100 is
comprised of a plurality of layers of amorphous metal strip
material 20 that are each substantially the same size and shape.
The strip material 20 is stacked, laminated together and then
annealed.
[0029] The magnetic component 200 depicted in FIG. 2B includes at
least one, and preferably two oppositely disposed arcuate surfaces
210. The arcuately-shaped component 200 is comprised of a plurality
of layers of amorphous metal strip material 20 that are each
substantially the same size and shape and that are stacked,
laminated together, and annealed.
[0030] The bulk amorphous metal magnetic component 300 depicted in
FIG. 2C may be used as a stator for a radial gap electric motor and
is comprised of six pieces of magnetic component 100 and six pieces
of magnetic component 200.
[0031] The bulk amorphous metal magnetic component 400 depicted in
FIG. 3A is generally circular and includes a plurality of generally
rectangular teeth 410 that extend radially inward toward the center
of the circular component 400. The component 400 is comprised of a
plurality of layers of amorphous metal strip material 20 that are
each substantially the same size and shape and that are stacked,
laminated together, and then annealed. A bulk amorphous metal
component constructed in accordance with the embodiment of FIG. 3A
may be used as a stator in a radial air gap electric motor.
[0032] The bulk amorphous metal component 500 depicted in FIG. 3B
is generally disc-shaped and includes a plurality of generally
rectangular teeth 510 that extend radially outward. The component
500 is comprised of a plurality of layers of amorphous metal strip
material 20 that are each substantially the same size and shape and
that are stacked, laminated together, and then annealed. A bulk
amorphous metal component constructed in accordance with the
embodiment of FIG. 3B may be used as a rotor in a radial air gap
electric motor.
[0033] Referring next to FIG. 3C, a stator 400 and rotor 500 are
constructed as bulk amorphous metal components in accordance with
the present invention and used as part of a high efficiency radial
air gap electric motor 600.
[0034] The present invention also provides a method of constructing
a bulk amorphous metal component. As shown in FIG. 4, a roll 30 of
amorphous metal strip material is cut by cutting blades 40 into a
plurality of strips 20 having the same shape and size. The strips
20 are stacked to form a bar 50 of stacked amorphous metal strip
material. The bar 50 is annealed, impregnated with an epoxy resin
and cured. The bar 50 can be cut along the lines 52 depicted in
FIG. 5 to produce a plurality of generally trapezoidally-shaped
magnetic components 10. The finished magnetic component 10 may be
generally rectangular, trapezoidal, square, or other polyhedral
shape. The bar 50 may also be cut to produce three dimensional
shapes in the form of pentagonal prisms 11, arc-shaped blocks 12,
circular-shaped blocks 13 or disc-shaped blocks 14, as shown in
FIG. 2A, 2B, 3A and 3B respectively.
[0035] In a second embodiment of the method of the present
invention, shown in FIGS. 6 and 7, a bulk amorphous metal magnetic
component 10 is formed by winding a single amorphous metal strip 22
or a group of amorphous metal strips 22 around a generally
rectangular mandrel 60 to form a generally rectangular wound core
70. The height of the short sides 74 of the core 70 is preferably
approximately equal to the desired length of the finished bulk
amorphous metal magnetic component 10. The core 70 is annealed,
impregnated with an epoxy resin and cured. Two components 10 may be
formed by cutting the short sides 74, leaving the radiused corners
76 on the long sides 78. Additional magnetic components 10 may be
formed by removing the radiused corners 76 from the long sides 78,
and cutting the long sides 78 at a plurality of locations,
indicated by the dashed lines 72. In the example illustrated in
FIG. 7, the bulk amorphous metal component 10 has a generally
rectangular shape, although other shapes are contemplated by the
present invention. The wound core 70 may also be cut to produce
three dimensional shapes in the form of pentagonal prisms 11,
arc-shaped blocks 12, circular-shaped blocks 13 or disc-shaped
blocks 14, as shown in FIG. 2A, 2B, 3A and 3B respectively.
[0036] Construction in this manner is especially suited for
magnetic components such as amorphous metal stator and rotor
assemblies in electric motors. Magnetic component manufacturing is
simplified and manufacturing time is reduced. Stresses otherwise
encountered during the construction of bulk amorphous metal
components are minimized. Magnetic performance of the finished
components is optimized.
[0037] The bulk amorphous metal magnetic component 10 of the
present invention can be manufactured using numerous amorphous
metal alloys. Generally stated, the alloys suitable for use in the
component 10 construction of the present invention are defined by
the formula: M.sub.70-85 Y.sub.5-20 Z.sub.0-20, subscripts in atom
percent, where "M" is at least one of Fe, Ni and Co, "Y" is at
least one of B, C and P, and "Z" is at least one of Si, Al and Ge;
with the proviso that (i) up to ten (10) atom percent of component
"M" can be replaced with at least one of the metallic species Ti,
V, Cr, Mn, Cu, Zr, Nb, Mo, Ta and W, and (ii) up to ten (10) atom
percent of components (Y+Z) can be replaced by at least one of the
non-metallic species In, Sn, Sb and Pb. Highest induction values at
low cost are achieved for alloys wherein "M" is iron, "Y" is boron
and "Z" is silicon. For this reason, amorphous metal strip composed
of iron-boron-silicon alloys is preferred. Most preferred is
amorphous metal strip having a composition consisting essentially
of about 11 atom percent boron and about 9 atom percent silicon,
the balance being iron and incidental impurities. This strip is
sold by AlliedSignal Inc. under the trade designation METLAS.RTM.
alloy 2605SA-1.
[0038] The bulk amorphous metal magnetic component 10 of the
present invention can be cut from bars 50 of stacked amorphous
metal strip or from cores 70 of wound amorphous metal strip using
numerous cutting technologies. The component 10 may be cut from the
bar 50 or core 70 using a cutting blade or wheel. Alternately, the
component 10 may be cut by electro-discharge machining or with a
water jet.
[0039] Bulk amorphous magnetic components will magnetize and
demagnetize more efficiently than components made from other
iron-base magnetic metals. When used as the rotor or stator in an
electric motor, the bulk amorphous metal component will generate
less heat than a comparable component made from another iron-base
magnetic metal when the two components are magnetized at identical
induction and frequency. The electric motor using the bulk
amorphous metal component can therefore be designed to operate 1)
at a lower operating temperature; 2) at higher induction to achieve
reduced size and weight; or, 3) at higher frequency to achieve
reduced size and weight, or to achieve superior motion control,
when compared to electric motors using components made from other
iron-base magnetic metals.
[0040] The following example is presented to provide a more
complete understanding of the invention. The specific techniques,
conditions, materials, proportions and reported data set forth to
illustrate the principles and practice of the invention are
exemplary and should not be construed as limiting the scope of the
invention.
EXAMPLE 1
Preparation And Electro-Magnetic Testing of
an Amorphous Metal Rectangular Prism
[0041] Fe.sub.80B.sub.11Si.sub.9 amorphous metal ribbon,
approximately 60 mm wide and 0.022 mm thick, was wrapped around a
rectangular mandrel or bobbin having dimensions of approximately 25
mm by 90 mm. Approximately 800 wraps of amorphous metal ribbon were
wound around the mandrel or bobbin producing a rectangular core
form having inner dimensions of approximately 25 mm by 90 mm and a
build thickness of approximately 20 mm. The core/bobbin assembly
was annealed in a nitrogen atmosphere. The anneal consisted of: 1)
heating the assembly up to 365.degree. C.; 2) holding the
temperature at approximately 365.degree. C. for approximately 2
hours; and, 3) cooling the assembly to ambient temperature. The
rectangular, wound, amorphous metal core was removed from the
core/bobbin assembly. The core was vacuum impregnated with an epoxy
resin solution. The bobbin was replaced, and the rebuilt,
impregnated core/bobbin assembly was cured at 120.degree. C. for
approximately 4.5 hours. When fully cured, the core was again
removed from the core/bobbin assembly. The resulting rectangular,
wound, epoxy bonded, amorphous metal core weighed approximately
2100 g.
[0042] A rectangular prism 60 mm long by 40 mm wide by 20 mm thick
(approximately 800 layers) was cut from the epoxy bonded amorphous
metal core with a 1.5 mm thick cutting blade. The cut surfaces of
the rectangular prism and the remaining section of the core were
etched in a nitric acid/water solution and cleaned in an ammonium
hydroxide/water solution.
[0043] The remaining section of the core was etched in a nitric
acid/water solution and cleaned in an ammonium hydroxide/water
solution. The rectangular prism and the remaining section of the
core were then reassembled into a full, cut core form. Primary and
secondary electrical windings were fixed to the remaining section
of the core. The cut core form was electrically tested at 60 Hz,
1,000 Hz, 5,000 Hz and 20,000 Hz and compared to catalogue values
for other ferromagnetic materials in similar test configurations
[National Arnold Magnetics, 17030 Muskrat Avenue, Adelanto, Calif.
92301 (1995)]. The results are compiled below in Tables 1, 2, 3 and
4.
1TABLE 1 Core Loss @ 60 Hz (W/kg) Material Crystalline Crystalline
Crystalline Crystalline Fe--3% Si Fe--3% Si Fe--3% Si Fe--3% Si (25
.mu.m) (50 .mu.m) (175 .mu.m) (275 .mu.m) Amorphous National-Arnold
National-Arnold National-Arnold National-Arnold Flux
Fe.sub.80B.sub.11Si.sub.9 Magnetics Magnetics Magnetics Magnetics
Density (22 .mu.m) Silectron Silectron Silectron Silectron 0.3 T
0.10 0.2 0.1 0.1 0.06 0.7 T 0.33 0.9 0.5 0.4 0.3 0.8 T 1.2 0.7 0.6
0.4 1.0 T 1.9 1 0 0.8 0.6 1.1 T 0.59 1.2 T 2.6 1.5 1.1 0.8 1.3 T
0.75 1.4 T 0.85 3.3 1.9 1.5 1.1
[0044]
2TABLE 2 Core Loss @ 1,000 Hz (W/kg) Material Crystalline
Crystalline Crystalline Crystalline Fe--3% Si Fe--3% Si Fe--3% Si
Fe--3% Si (25 .mu.m) (50 .mu.m) (175 .mu.m) (275 .mu.m) Amorphous
National-Arnold National-Arnold National-Arnold National-Arnold
Flux Fe.sub.80B.sub.11Si.sub.9 Magnetics Magnetics Magnetics
Magnetics Density (22 .mu.m) Silectron Silectron Silectron
Silectron 0.3 T 1.92 2.4 2.0 3.4 5.0 0.5 T 4.27 6.6 5 5 8.8 12 0.7
T 6.94 13 9.0 18 24 0.9 T 9.92 20 17 28 41 1.0 T 11.51 24 20 31 46
1.1 T 13.46 1.2 T 15.77 33 28 1.3 T 17.53 1 4 T 19.67 44 35
[0045]
3TABLE 3 Core Loss @ 5,000 Hz (W/kg) Material Crystalline
Crystalline Crystalline Fe-3% Si Fe-3% Si Fe-3% Si (25 .mu.m) (50
.mu.m) (175 .mu.m) National- National- National- Amorphous Arnold
Arnold Arnold Flux Fe.sub.80B.sub.11Si.sub.9 Magnetics Magnetics
Magnetics Density (22 .mu.m) Silectron Silectron Silectron 0.04 T
0.25 0.33 0.33 1.3 0.06 T 0.52 0.83 0.80 2.5 0.08 T 0.88 1.4 1.7
4.4 0.10 T 1.35 2.2 2.1 66 0.20 T 5 8.8 8.6 24 0.30 T 10 18.7 18.7
48
[0046]
4TABLE 4 Core Loss @ 20,000 Hz (W/kg) Material Crystalline
Crystalline Crystalline Fe-3% Si Fe-3% Si Fe-3% Si (25 .mu.m) (50
.mu.m) (175 .mu.m) National- National- National- Amorphous Arnold
Arnold Arnold Flux Fe.sub.80B.sub.11Si.sub.9 Magnetics Magnetics
Magnetics Density (22 .mu.m) Silectron Silectron Silectron 0.04 T
1.8 2.4 2.8 16 0.06 T 3.7 5.5 7.0 33 0.08 T 6.1 9.9 12 53 0.10 T
9.2 15 20 88 0.20 T 35 57 82 0.30 T 70 130
EXAMPLE 2
Preparation of an Amorphous Metal Trapezoidal Prism
[0047] Fe.sub.80B.sub.11Si.sub.9 amorphous metal ribbon,
approximately 48 mm wide and 0.022 mm thick, was cut into lengths
of approximately 300 mm. Approximately 3,800 layers of the cut
amorphous metal ribbon were stacked to form a bar approximately 48
mm wide and 300 mm long, with a build thickness of approximately 96
mm. The bar was annealed in a nitrogen atmosphere. The anneal
consisted of: 1) heating the bar up to 365.degree. C.; 2) holding
the temperature at approximately 365.degree. C. for approximately 2
hours; and, 3) cooling the bar to ambient temperature. The bar was
vacuum impregnated with an epoxy resin solution and cured at
120.degree. C. for approximately 4.5 hours. The resulting stacked,
epoxy bonded, amorphous metal bar weighed approximately 9000 g.
[0048] A trapezoidal prism was cut from the stacked, epoxy bonded
amorphous metal bar with a 1.5 mm thick cutting blade. The
trapezoid-shaped face of the prism had bases of 52 and 62 mm and
height of 48 mm. The trapezoidal prism was 96 mm (3,800 layers)
thick. The cut surfaces of the trapezoidal prism and the remaining
section of the core were etched in a nitric acid/water solution and
cleaned in an ammonium hydroxide/water solution.
EXAMPLE 3
Preparation of Polygonal, Bulk Amorphous Metal Components
With Arc-Shaped Cross-Sections
[0049] Fe.sub.81B.sub.11Si.sub.9 amorphous metal ribbon,
approximately 50 mm wide and 0.022 mm thick, was cut into lengths
of approximately 300 mm. Approximately 3,800 layers of the cut
amorphous metal ribbon were stacked to form a bar approximately 50
mm wide and 300 mm long, with a build thickness of approximately 96
mm. The bar was annealed in a nitrogen atmosphere. The anneal
consisted of: 1) heating the bar up to 365.degree. C.; 2) holding
the temperature at approximately 365.degree. C. for approximately 2
hours; and, 3) cooling the bar to ambient temperature. The bar was
vacuum impregnated with an epoxy resin solution and cured at
120.degree. C. for approximately 4.5 hours. The resulting stacked,
epoxy bonded, amorphous metal bar weighed approximately 9200 g.
[0050] The stacked, epoxy bonded, amorphous metal bar was cut using
electro-discharge machining to form a three-dimensional, arc-shaped
block. The outer diameter of the block was approximately 96 mm. The
inner diameter of the block was approximately 13 mm. The arc length
was approximately 90.degree.. The block thickness was approximately
96 mm.
[0051] Fe.sub.81B.sub.11Si.sub.9 amorphous metal ribbon,
approximately 20 mm wide and 0.022 mm thick, was wrapped around a
circular mandrel or bobbin having an outer diameter of
approximately 19 mm. Approximately 1,200 wraps of amorphous metal
ribbon were wound around the mandrel or bobbin producing a circular
core form having an inner diameter of approximately 19 mm and an
outer diameter of approximately 48 mm. The core had a build
thickness of approximately 29 mm. The core was annealed in a
nitrogen atmosphere. The anneal consisted of: 1) heating the bar up
to 365.degree. C.; 2) holding the temperature at approximately
365.degree. C. for approximately 2 hours; and, 3) cooling the bar
to ambient temperature. The core was vacuum impregnated with an
epoxy resin solution and cured at 120.degree. C. for approximately
4.5 hours. The resulting wound, epoxy bonded, amorphous metal core
weighed approximately 71 g.
[0052] The wound, epoxy bonded, amorphous metal core was cut using
a water jet to form a semi-circular, three dimensional shaped
object. The semi-circular object had an inner diameter of
approximately 19 mm, an outer diameter of approximately 48 mm, and
a thickness of approximately 20 mm.
[0053] The cut surfaces of the polygonal bulk amorphous metal
components were etched in a nitric acid/water solution and cleaned
in an ammonium hydroxide/water solution.
[0054] Having thus described the invention in rather full detail,
it will be understood that such detail need not be strictly adhered
to but that various changes and modifications may suggest
themselves to one skilled in the art, all falling within the scope
of the present invention as defined by the subjoined claims.
* * * * *