U.S. patent number 3,856,513 [Application Number 05/318,146] was granted by the patent office on 1974-12-24 for novel amorphous metals and amorphous metal articles.
This patent grant is currently assigned to Allied Chemical Corporation. Invention is credited to Ho-Sou Chen, Donald E. Polk.
United States Patent |
3,856,513 |
Chen , et al. |
December 24, 1974 |
NOVEL AMORPHOUS METALS AND AMORPHOUS METAL ARTICLES
Abstract
Novel metal alloy compositions which are obtained in the
amorphous state and are superior to such previously known alloys
based on the same metals are provided; these new compositions are
easily quenched to the amorphous state and possess desirable
physical properties. Also disclosed is a novel article of
manufacture in the form of wire of these novel amorphous metal
alloys and of other compositions of the same type.
Inventors: |
Chen; Ho-Sou (Warren, NJ),
Polk; Donald E. (Morristown, NJ) |
Assignee: |
Allied Chemical Corporation
(New York, NY)
|
Family
ID: |
23236859 |
Appl.
No.: |
05/318,146 |
Filed: |
December 26, 1972 |
Current U.S.
Class: |
148/403; 164/462;
164/463; 420/14; 420/424; 420/441; 420/580; 252/519.1; 252/519.14;
164/423; 164/480; 420/28; 420/435; 420/445; 420/588; 374/176 |
Current CPC
Class: |
C22C
27/06 (20130101); H05K 9/009 (20130101); C22C
45/02 (20130101); H01C 3/005 (20130101); C22C
45/00 (20130101); C22C 27/025 (20130101); H01F
1/15391 (20130101); C22C 19/00 (20130101); B22D
11/005 (20130101) |
Current International
Class: |
C22C
45/02 (20060101); C22C 27/00 (20060101); C22C
27/06 (20060101); H01C 3/00 (20060101); H01F
1/153 (20060101); B22D 11/00 (20060101); C22C
19/00 (20060101); C22C 45/00 (20060101); C22C
27/02 (20060101); H01F 1/12 (20060101); H05K
9/00 (20060101); C22c 001/00 (); C22c 019/00 ();
C22c 031/00 (); C22c 037/00 (); C22c 039/00 () |
Field of
Search: |
;75/123B,123D,123K,123L,123CB,123V,122,170,124,134F,134D,134V,126A |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Rutledge; L. Dewayne
Assistant Examiner: Steiner; Arthur J.
Attorney, Agent or Firm: Plantamura; Arthur J.
Claims
We claim:
1. A metal alloy of the formula M.sub.a Y.sub.b Z.sub.c which is at
least 50 percent amorphous and wherein M is a metal selected from
the group consisting essentially of iron, nickel, chromium, cobalt,
or vanadium or a mixture thereof, Y is a metalloid selected from
the group consisting of phosphorus, carbon and boron or a mixture
thereof, and Z is an element selected from the group consisting of
aluminum, silicon, tin, antimony, germanium, indium, and beryllium
and mixtures thereof, "a", "b" and "c" are atomic percentages
ranging from about 60 to 90, 10 to 30 and 0.1 to 15 respectively
with the proviso that a plus b plus c equals 100.
2. The amorphous metal alloy of claim 1 wherein "a," "b" and "c"
range from 69 to 84.5, 15 to 25, and 0.5 to 6, respectively.
3. The amorphous metal alloy of claim 1 wherein up to about
one-fourth of the metal M is replaced by elements commonly alloyed
with iron or nickel.
4. As an article of manufacture, sheets,ribbons and powders of the
amorphous metals having the compositions of claim 1.
5. As an article of manufacture, sheets, ribbons and powders of the
amorphous metals having the compositions of claim 3.
6. As an article of manufacture, a metal wire comprising an alloy
which is at least 50 percent amorphous and having a composition of
the formula T.sub.i X.sub.j wherein T is a transition metal or
mixture of said transition metals and X is an element selected from
the group consisting of aluminum, antimony, beryllium, boron,
germanium, carbon, indium, phosphorus, silicon, tin, and mixtures
thereof and wherein i and j are in atomic percentages and range
from about 70 to about 87 and from about 13 to about 30
respectively.
7. The article of claim 6 wherein i ranges from about 74 to about
84 and j ranges from about 16 to about 26.
8. Amorphous metal wire of claim 6 wherein iron comprises at least
60 atomic percent of T.
Description
BACKGROUND OF THE INVENTION
This invention relates to novel amorphous metal compositions and to
the preparation of wires of these and other amorphous metal
alloys.
Heretofore, a limited number of amorphous, i.e., noncrystalline or
glassy, metal alloys have been prepared. To obtain the amorphous
state, a molten alloy of a suitable composition must be quenched
rapidly, or alternatively, a deposition technique must be used:
suitably employed vapor deposition, sputtering, electrodeposition,
or chemical (electro-less) deposition can be used to produce the
amorphous metal.
The production of amorphous metal by these known techniques, i.e.,
either through a rapid quench of the melt or by deposition,
severely limits the form in which the amorphous metal can be
obtained. For example, when the amorphous metal is obtained from
the melt, the rapid quench has generally been achieved by spreading
the molten alloy in a thin layer against a metal substrate such as
Cu or Al held at or below room temperature. The molten metal is
typically spread to a thickness of about 0.002 inch which, as
discussed in detail by R. Predecki, A. W. Mullendore and N. J.
Grant in Trans. AIME 233, 1581 (1965) and R. C. Ruhl in Mat. Sci.
& Eng. 1, 313 (1967), leads to a cooling rate of about 10.sup.6
.degree.C/sec.
Various procedures have been proposed to provide rapid quenching by
spreading the molten liquid in a thin layer against a metal
substrate. Typical examples of such techniques are the gun
technique of P. Duwez and R. H. Willens described in Trans. AIME
227, 362 (1963) in which a gaseous shock wave propels a drop of
molten metal against a substrate made of a metal such as copper;
the piston and anvil technique described by P. Pietrokowsky in Rev.
Sci. Instr. 34, 445 (1963) in which two metal plates come together
rapidly and flatten out and quench a drop of molten metal falling
between them; the casting technique described by R. Pond, Jr. and
R. Maddin in Trans. Met. Soc. AIME 245, 2475 (1969) in which a
molten metal stream impinges on the inner surface of a rapidly
rotating hollow cylinder open at one end; and the rotating double
rolls technique described by H. S. Chen and C. E. Miller in Rev.
Sci. Instrum. 41, 1237 (1970) in which the molten metal is squirted
into the nip of a pair of rapidly rotating metal rollers. These
techniques produce small foils or ribbon-shaped samples in which
one dimension is much smaller than the other two so that their
usefulness as a practical matter is severely limited. Because of
the high cooling rates necessary to obtain the amorphous state from
quenched liquid alloys, it is required that the amorphous metals be
formed in a shape which does not preclude adequate quenching, i.e.,
they must have at least one dimension small enough to permit the
sufficiently rapid removal of the heat from the sample.
Metal alloys which are most easily obtained in the amorphous state
by rapid quenching or by deposition techniques are mixtures of
transition metals with metalloids, i.e. semimetals. In each case,
the alloy is approximately 80 atomic percent transition metal and
20 atomic percent metalloid. Examples of alloys of this type
reportedly made previously in the amorphous state are Pd.sub.84
Si.sub.16, Pd.sub.79 Si.sub.21, Pd.sub.77.5 Cu.sub.6 Si.sub.16.5,
Co.sub.80 P.sub.20, Au.sub.76.9 Ge.sub.13.65 Si.sub.9.45,
Ni.sub.81.4 P.sub.18.6, Fe.sub.80 P.sub.13 C.sub.7, Ni.sub.15
Pt.sub.60 P.sub.25, Ni.sub.42.5 Pd.sub.42.5 P.sub.15, Fe.sub.75
P.sub.15 C.sub.10, Mn.sub.75 P.sub.15 C.sub.10, Ni.sub.80 S.sub.20,
and Ni.sub.78 B.sub.22 where the subscripts indicate atomic
percent.
The cooling rate necessary to achieve the amorphous state, i.e., to
avoid crystallization, and the stability of the amorphous state
once it is obtained depends upon the composition of the alloy. Some
of these alloys are better glass formers than others; these
"better" alloys can be obtained in the amorphous state with a lower
cooling rate, which in practice may be more readily obtainable, or
can be obtained with a greater thickness when quenched from the
melt with a given technique.
Generally, there is a small range of compositions surrounding each
of the known amorphous compositions where the amorphous state can
be obtained. However, apart from quenching the alloys, no practical
guideline is known for predicting with certainty which of the
multitude of different alloys will yield an amorphous metal with
given processing conditions and hence which of the alloys are
"better" glass formers.
The amorphous and the crystalline state are distinguished by the
respective absence or presence of long range periodicity. Further,
the compositional ordering in alloys may be different for the two
states. These differences are reflected in the differences in their
x-ray diffraction behavior, and accordingly, x-ray diffraction
measurements are most often used to distinguish a crystalline from
an amorphous substance. Diffractometer traces of an amorphous
substance reveal a slowly varying diffracted intensity, in many
respects similar to a liquid, while crystalline materials produce a
much more rapidly varying diffracted intensity. Also, the physical
properties, which depend upon the atomic arrangement, are uniquely
different for the crystalline and the amorphous state. The
mechanical properties differ substantially for the two states; for
example, a 0.002 inch thick strip of amorphous Pd.sub.80 Si.sub.20
is relatively more ductile and stronger and will deform plastically
upon sufficiently severe bending while a similar crystalline strip
of the same composition is brittle and weak and will fracture upon
identical bending. Further, the magnetic and electrical properties
of the two states are different. In each case, the metastable
amorphous state will convert to a crystalline form upon heating to
a sufficiently high temperature with the evolution of a heat of
crystallization.
It should be noted, moreover, that cooling a molten metal to a
glass is distinctly different from cooling such a molten metal to
the crystalline state. When a liquid is cooled to a glass, the
liquid solidifies continuously over a range of temperature without
a discontinuous evolution of a heat of fusion. In contrast,
crystallization is a thermodynamic first order transition and thus
is associated with a heat of fusion and a specific temperature.
SUMMARY OF THE INVENTION
An object of the invention is to provide a novel amorphous metal
compositions which are readily quenched to the amorphous state,
have increased stability, and possess desirable physical
properties.
A further object of the invention resides in the provision of
articles of manufacture of these novel amorphous metals in a
variety of forms, e.g., ribbons, sheets, wire, powder, etc.
Another object of the invention is to provide an article of these
and other amorphous metal compositions in the form of wire, i.e., a
filament with a cross-section which is approximately circular,
i.e., a rod-like filament, as contrasted with strands which are
ribbon like.
Additional objects and advantages will become apparent from the
description and examples provided.
The novel compositions of interest in this invention are composed
primarily of Fe, Ni, Cr, Co, and V. Although certain compositions,
i.e. Fe.sub.75 P.sub.15 C.sub.10, Fe.sub.80 P.sub.13 C.sub.7,
Fe.sub.80 P.sub.13 B.sub.7, Co.sub.73 P.sub.15 B.sub.12, Fe.sub.76
B.sub.17 C.sub.7 and Ni.sub.75 P.sub.15 B.sub.10, have been
previously described as being quenched from the melt to the
amorphous state, we have discovered that certain novel, distinct
and useful compositions may be obtained by the addition of small
amounts, i.e., from 0.1 to 15 atomic percent but preferably from
0.5 to 6 atomic percent, of certain elements such as Al, Si, Sn,
Sb, Ge, In, or Be, to such alloys. As a consequence of the
introduction of these elements, these alloys become much better
glass formers, i.e., the amorphous state is more readily obtained
and moreover, is more thermally stable.
We have found that the inclusion of small amounts of certain
elements of a group hereafter sometimes referred to by the symbol
"Z," and consisting of Al, Si, Sn, Ge, In, Sb or Be, in amounts of
from about 0.1 to about 15 atomic percent, to alloys of the
type
M.sub.k Y.sub.p
wherein M is a metal selected from one or more of the group
consisting of Fe, Ni, Co, V and Cr; and Y represents elements from
the group consisting of P, B, and C; (k) and (p) are in atomic
percent and are about 70 to 85 and about 30 to 15,
respectively,
provides superior glass forming alloys. Illustrative alloys, for
example, are Fe.sub.76 P.sub.15 C.sub.5 Si.sub.1 Al.sub.3,
Fe.sub.39 Ni.sub.39 P.sub.14 B.sub.6 Al.sub.2, Ni.sub.74 P.sub.16
B.sub.6 Al.sub.4, and Cr.sub.15 Co.sub.15 Ni.sub.45 P.sub.16
B.sub.6 Al.sub.3 and may have the general formula:
M.sub.a Y.sub.b Z.sub.c
wherein M, Y, and Z are as defined above and a, b, and c are in
atomic percent and range from about 60 to 90, about 10 to 30 and
about 0.1 to 15, respectively, and a plus b plus c equals 100.
Additionally, we have discovered that the alloy Fe.sub.35 Ni.sub.45
P.sub.15 B.sub.6 and those alloys of similar compositions (e.g.
Fe.sub.44 Ni.sub.35 P.sub.13 B.sub.7 C.sub.1, FE.sub.40 Ni.sub.40
P.sub.14 B.sub.6, Fe.sub.30 Ni.sub.50 P.sub.16 B.sub.6) are
superior glass forming alloys.
Selected alloys of the kinds disclosed above may be relatively more
consistently and more readily quenched to the amorphous state than
previously thought possible with known Fe-Ni-Co- based alloys.
Moreover, these alloys are more stable; upon heating, they show the
thermal manifestation of the glass transition (a sudden increase in
the specific heat) while previously known Fe-Ni-Co- based alloys do
not. Typically, amorphous alloys which show this thermal
manifestation of the glass transition are more readily obtained in
the amorphous state than amorphous alloys which do not.
The compositions within the contemplation of the present invention
can be obtained in the form of ribbons or strips using the
apparatus described in the above-mentioned references, Pond and
Maddin, or that of Chen and Miller, or other techniques which are
similar in principle. Further, wider strips or sheets can be
obtained with similar quench tenchiques when the molten metal is
squirted as a sheet, for example, rather than with an approximately
round cross section. Additionally, powders of such amorphous metlas
where the particle size ranges from about 0.0004 to 0.010 inch can
be made by atomizing the molten alloy to droplets of this size and
then quenching these droplets in a liquid such as water,
refrigerated brine, or liquid nitrogen.
The alloys discussed above in each case are made from the high
purity elements. however, in the utilization of these alloys, it is
anticipated that the alloys would be made from the less expensive
commercially available material which would have small amounts of
other elements in solution. Thus the alloys contemplated by the
invention may contain fractional amounts of other elements which
are commonly found in commercially available Fe or Ni alloys, for
example, either as a result of the source of the primary metal or
through a later addition. Examples of such elements are Mo, Ti, Mn,
W, Zr, Hf and Cu.
In addition to the novel amorphous compositions described herein,
the invention contemplates a novel article of manufacture in the
form of amorphous metal wires of these alloys and others of the
transition metal-metalloid type. In providing the wire-form
article, a stream of molten metal is formed by squirting the molten
metal from a nozzle or otherwise forming a jet from a suitable die
and appropriately quenching the alloy.
Suitable compositions from which such wires are made may be
represented by the general formula
T.sub.i X.sub.j
wherein T is a transition metal or mixture of said transition
metals and X is an element selected from the group consisting of
phosphorus, boron, carbon, aluminum, silicon, tin, germanium,
indium, beryllium and antimony and mixtures thereof and wherein i
and j are atomic percent and range from about 70 to 87 and from
about 13 to 30, respectively. It will be understood that not every
alloy encompassed within the formula T.sub.i X.sub.j will
necessarily yield an amorphous product. For example, a given
composition may form a crystalline wire with a particular quenching
technique and diameter, while an amorphous wire may be formed with
a different quenching technique which provides a higher cooling
rate and/or with a smaller diameter. Additionally, some specific
ratios within the general formula T.sub.i X.sub.j cannot be
quenched from the melt to a wire of diameter large enough to be
useful.
While most metal wire is conventionally prepared by drawing the
metal through successively smaller dies, such a technique is not
appropriate in the production of wire of amorphous metals.
Amorphous metals, because of the manner in which they must be
obtained, are not available in the form and dimensions required of
the starting materials which are to be drawn to wires.
The quenching of the molten jet to form an amorphous metal wire has
been achieved by squirting the molten jet into stationary water or
refrigerated brine. however, any process may be used to quench the
molten jet to the amorphous state as long as the cooling rate is
great enough to avoid crystallization and disruption of the molten
jet from the wire form does not take place during cooling. The
cooling rate experienced by the molten metal stream or jet during
quenching is dependent upon both the technique used to cool the
molten jet and the diameter of the jet; the cooling technique
determines the rate at which heat is removed from the surface of
the jet while the diameter determines the surface-to-volume ratio
and hence the quantity of heat which must be removed per unit area
to reduce the temperature a given amount. As noted heretofore,
different compositions require different minimum cooling rates in
order to obtain the amorphous state. Thus, in order to obtain an
amorphous, as distinguished from crystalline, metal wire, the
cooling technique, the jet diameter, and the alloy composition must
be reconciled.
The amorphous metal wire contemplated by the invention may be
derived from a range of compositions of the transition
metalmetalloid type alloys including the novel compositions
described above, previously inown amorphous compositions, from
which wire form articles have not previously been prepared, as well
as from other alloy compositions of the type T.sub.i X.sub.j.
The production of amorphous metal wires yields a number of
advantages because of their unique properties which are not
possessed by crystalline metal wires produced by ordinary
techniques. For example, glassy metal wires are less sensitive than
crystalline wire to radiation damage and have a small or even
negative temperature coefficient of resistivity. In preparing the
novel amorphous alloy compositions of the invention, important
processing economies are also available; the amorphous wire form of
certain compositions may be less expensive for the sizes and
strengths which can be obtained than the commonly used drawn wire.
The amorphous metal strands, wires, sheets, etc., contemplated by
the invention, find a variety of uses such as reinforcement use,
e.g. as tire cord or as reinforcement in molded thermoplastic or
thermosetting plastics; as filter media; biomedical reinforcement,
e.g. sutures; as relay magnets; corrosion resistant chemical
processing equipment; and the like.
Typically, in accordance with the invention, wires of about 0.005
inch diameter are formed, although the invention is not restricted
to such diameter. Additionally, these alloys are ideally suited for
the melt spinning of wire since they are generally of a
near-eutectic composition and hence have a relatively low liquidus
temperature, i.e. the lowest temperature at which the alloy is
totally liquid in equilibrium. This simplifies the processing of
the alloy and expands the list of materials which can be used to
contain the molten alloy and as nozzles or dies to form the molten
stream. For example, Fe.sub.76 P.sub.16 C.sub.4 Al.sub.4, which is
86.7 weight percent Fe, has a liquidus temperature of about
1020.degree.C while pure Fe melts at 1535.degree.C.
Various processes can be used to achieve the necessary cooling to
yield the amorphous alloys. As stated above, the stream of the
molten jet may be squirted into stationery water or refrigerated
brine and appropriately collected therefrom after it is quenched.
Typical of other specific processes which may be adapted to produce
amorphous metal wire in accordance with the invention include that
process described by S. Kavesh in a copending U.S. Pat.
application, Ser. No. 306,472, filed Nov. 14, 1972; those by R. D.
Schile in U.S. Pat. Nos. 3,461,943 and 3,543,831; and that
described by S. A. Dunn, et al. in U.S. Pat. No. 3,658,979. While
these same methods may be employed to yield either crystalline or
amorphous metal, one skilled in the art would experience no
difficulty in accordance with the teaching presented herein
regarding the use of appropriate cooling rates, wire diameters and
compositions so as to obtain an amorphous metal wire.
These amorphous alloys and wire form articles have very desirable
physical properties. For example, high tensile strengths and a high
elastic limit in the as-quenched state can be achieved as well as
good corrosion resistance and unique magnetic properties in various
selected compositions. Also, a number of compositions are found to
be remarkably ductile in the amorphous state. Some specimens, for
example, can be bent over radii of curvature less than their
thickness and can be cut with scissors. Also, with these ductile
samples, tensile strengths of up to 350,000 psi have been obtained
in the as-quenched condition. Thus, the heat treatments often given
crystalline materials to obtain high strength are obviated with the
amorphous metal alloys. Alloys such as Fe.sub.76 P.sub.15 C.sub.4
B.sub.1 Si.sub.1 Al.sub.3 can be quenched directly from the melt to
form inexpensive, high strength wire which can be employed directly
as a commercial product.
The amorphous alloys provide strong, corrosion-resistant material;
selected compositions of these amorphous alloys are relatively
unreactive with concentrated surfuric, hydrochloric, or nitric
acid. For example, amorphous Fe.sub.40 Ni.sub.38 P.sub.14 B.sub.6
Al.sub.2 is found to be several orders of magnitude less reactive
than stainless steels with concentrated hydrochloric acid.
Further, it has been found that various of the metal alloys of the
same general formula T.sub.i X.sub.j considered above also have the
desirable properties of high strength and hardness, ductility and
corrosion resistance even when they are partially crystalline. The
fraction of the sample that is crystalline can be estimated by
suitably employed x-ray or electron diffraction, electron
transmission microscopy, and thermal analysis. Hence, the invention
thus also contemplates a metal wire which is partially crystalline
but which is at least 50 percent amorphous. For example, such wires
may be rendered partially crystalline because the quenching rate is
lower than that required to obtain the totally amorphous state for
the specific composition being quenched.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Typically, the preferred novel amorphous compositions of the
invention are those characterized by the formula
M.sub.a Y.sub.b Z.sub.c (I)
wherein M is a metal selected from the group consisting of iron,
nickel, cobalt, chromium and vanadium and mixtures thereof; Y is an
element selected from the group consisting of phosphorus, boron and
carbon, and mixtures thereof; and Z is an element selected from the
group consisting of aluminum, antimony, beryllium, germanium,
indium, tin and silicon and mixtures thereof and wherein the
relative proportions in atomic percentages range from about 75 to
80, b from about 19 to 22, and c from 1 to 3.
These metals offer a variety of characteristics which may make them
suitable for a wide range of special applications. For example,
amorphous alloys in which M is totally or primarily iron, e.g.
Fe.sub.77 P.sub.15 C.sub.5 Si.sub.1 Al.sub.2, are of particular
interest because of their low cost and relatively high strength.
Amorphous alloys such as Ni.sub.48 Fe.sub.30 P.sub.14 B.sub.6
Al.sub.2 are of significance, for example, because of their special
ease of formation in combination with high strength and corrosion
resistance. Alloys which have a high chromium content, e.g.
Cr.sub.78 P.sub.14 B.sub.4 Si.sub.4, are exceptional in their
hardness and corrosion resistance.
The wire form amorphous metal alloy products of the invention
include the amorphous alloys defined by the formula (I) hereinabove
and contemplates also wire form products of other amorphous metals
as well and may be defined as those alloys having the formula
T.sub.i X.sub.j (II)
wherein T is a transition metal or mixture thereof and X is an
element selected from the group consisting of aluminum, antimony,
beryllium, boron, germanium, carbon, indium, phosphorus, silicon
and tin and mixtures thereof and wherein the proportion in atomic
percentages as represented by i and j are respectively from about
70 to about 87 and from about 13 to about 30 with the proviso that
i plus j equals 100. The transition metals T are those of group IB,
IIIB, IVB, VB, VIB, VIIB and VIII of the Periodic Chart of the
Elements and include the following: scandium, yttrium, lanthanum,
actinium, titanium, zirconium, hafnium, vanadium, niobium,
tantalum, chromium, molybdenum, tungsten, manganese, technetium,
rhenium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel,
palladium, platinum, copper, silver, and gold; preferably Fe, Ni,
Co, V, Cr, Pd, Pt and Ti.
The amorphous metal wires of composition T.sub.i X.sub.j are
typically from 0.001 to 0.020 inch in diameter, with diameters of
0.004 to 0.008 inch being preferred. Any suitable technique which
cools the molten jet sufficiently fast to avoid crystallization or
jet breakup can be used to quench the jet. The simplest such method
is to squirt the molten metal stream into a suitably chosen liquid
such as water or iced brine. An advantageous technique is that
described in the copending application of S. Kavesh, Ser. No.
306,472, filed Nov. 14, 1972, in which the molten jet is quenched
in a concurrently flowing stream of liquid. The novel compositions
and article of the invention are not limited by this process,
however, since various other processes which provide appropriate
quenching conditions may be utilized, such as the processes
described by R. D. Schile in U.S. Pat. Nos. 3,461,943 and
3,543,831, in which the cooling of the molten jet through corona
discharge, gas jets, and/or the deposition on the stream of a
colder substance are used.
The invention will be further described by the following specific
examples. It will be understood, however, that although these
examples may describe in detail certain preferred operating
variables and proportions within the contemplation of the
invention, they are provided primarily for purposes of illustration
and the invention in its broader aspects is not limited thereto.
Parts stated unless otherwise expressed are atomic percent.
EXAMPLE 1
Elemental Fe, P, C, Si and Al are weighed so that the product
mixture yields the following alloy: Fe.sub.76 P.sub.15 C.sub.5
Al.sub.3 Si.sub.1. The Fe, P and C were sintered for 1 day in an
evacuated sealed fused silica tube at 450.degree.C, then melted in
vacuum at 1050.degree.C. This alloy is remelted in vacuum at
1100.degree.C with the Si and Al to give the final alloy. This
alloy was placed in a fused silica tube with a 0.012 inch diameter
hole in the bottom and melted at 1,100.degree.C. A gas pressure of
8 psi is applied to the tube to force the molten metal through the
hole, and the stream of molten alloy is directed into the nip of
the rotating double rolls, held at room temperature, described by
Chen and Miller in Rev. Sci. Instrum. 41, 1237 (1970). The rolls
are two inches in diameter and were rotating at 1500 rpm. The
quenched metal was entirely amorphous as determined by x-ray
diffraction measurements, was ductile to bending and exhibited
tensile strengths to 350,000 psi. Alloys containing only Fe-P-C,
such as Fe.sub.80 P.sub.15 C.sub.5, Fe.sub.77 P.sub.16 C.sub.7, and
Fe.sub.75 P.sub.15 C.sub.10, similarly quenched, are brittle and
partially crystalline, as determined by x-ray diffraction. Further,
the amorphous Fe.sub.76 P.sub.15 C.sub.5 Al.sub.3 Si.sub.1 alloy
exhibits the thermal manifestation of the glass transition, i.e.
rapid increase in the specific heat, while amorphous Fe-P-C alloys
do not.
EXAMPLE 2
An alloy of composition Ni.sub.48 Fe.sub.30 P.sub.14 B.sub.6
Al.sub.2 is melted at 1,020.degree.C and quenched to an amorphous
metal in the manner of and following the procedure of Example 1. An
alloy with improved thermal stability and high bending ductility,
strength, and corrosion resistance is obtained. X-ray diffraction
measurements are used to confirm its amorphous structure.
EXAMPLE 3
The molten alloy of Example 2 is quenched to the amorphous state
using the Pond and Maddin teaching wherein the molten stream is
directed through a 0.020 inch hole onto the surface of a copper
hollow cylinder which is open at one end, has an inner diameter of
six inches, is at room temperature and is rotating at 2500 rpm. An
amorphous metal ribbon having the properties of that obtained in
Example 2 was obtained.
EXAMPLES 4 - 17
Following the procedures of Example 1, the amorphous alloys set
forth in Table I were obtained.
TABLE I ______________________________________ X-Ray Diffraction
Example No. Composition - Atomic % Analysis
______________________________________ 4 Fe.sub.76 P.sub.15 C.sub.5
Al.sub.3 amorphous 5 Fe.sub.75 P.sub.16 C.sub.3 B.sub.3 Al.sub.2
Si.sub.1 do. 6 Fe.sub.75 P.sub.15 C.sub.4 B.sub.1 Ge.sub.1 Sn.sub.1
Al.sub.3 do. 7 Fe.sub.39 Ni.sub.39 P.sub.14 B.sub.5 Si.sub.1
Al.sub.2 do. 8 Ni.sub.74 P.sub.16 B.sub.6 Al.sub.4 do. 9
Fe.sub.38.5 Ni.sub.38.5 P.sub.18 B.sub.2 Al.sub.1 Sb.sub.2 do. 10
Ni.sub.40 Co.sub.37 P.sub.15 B.sub.5 Si.sub.1 Al.sub.2 do. 11
Fe.sub.30 Cr.sub.20 V.sub.28 P.sub.14 B.sub.4 C.sub.2 Si.sub.2 do.
12 Fe.sub.76 P.sub.15 C.sub.5 Be.sub.2 Al.sub.2 do. 13 Fe.sub.27
Ni.sub.50 P.sub.14 B.sub.6 In.sub.1 Al.sub.2 do. 14 Fe.sub.40
Ni.sub.40 P.sub.14 B.sub.6 do. 15 Fe.sub.30 Ni.sub.50 P.sub.15
B.sub.6 do. 16 Fe.sub.45 Ni.sub.34 P.sub.14 B.sub.5 C.sub.2 do. 17
Fe.sub.35 Ni.sub.45 P.sub.17 B.sub.4 do.
______________________________________
EXAMPLE 18
The alloy of composition Ni.sub.75 P.sub.16 B.sub.6 Si.sub.3 was
obtained in the amorphous state by flash evaporation as follows: A
fine powder, .about.100 .mu. particles, of crystalline Ni.sub.75
P.sub.16 B.sub.6 Si.sub.3, was slowly sprinkled onto a hot tungsten
filament (.about.1,600.degree.C) in a vacuum of about
10.sup..sup.-6 mm Hg. The vaporized alloy was condensed onto a
nearby copper substrate kept at room temperature so that the
amorphous state of the same composition was achieved.
EXAMPLES 19 - 24
Following the procedure of Example 18, the amorphous alloys set
forth in Table II were obtained by flash evaporation.
TABLE II ______________________________________ X-Ray Diffraction
Example No. Composition - Atomic % Analysis
______________________________________ 19 Cr.sub.79 P.sub.14
B.sub.3 Si.sub.4 amorphous 20 Cr.sub.30 Ni.sub.47 P.sub.14 B.sub.6
Be.sub.3 do. 21 Cr.sub.76 P.sub.10 B.sub.10 Ge.sub.2 Si.sub.2 do.
22 Ni.sub.75 P.sub.16 B.sub.6 Al.sub.3 do. 23 Co.sub.78 P.sub.15
B.sub.5 Si.sub.2 do. 24 Ni.sub.41 Co.sub.41 P.sub.12 B.sub.4
Si.sub.2 do. ______________________________________
EXAMPLE 25
A Pd.sub.77.5 Cu.sub.6 Si.sub.16.5 alloy was melted in a fused
silica tube which had been drawn to a point with a 0.008 inch hole
at the tip and containing an argon atomosphere within a furnace
held at 870.degree.C. The melt was held in the tube by its surface
tension. The silica tube was rapidly lowered through the furnace so
that the tip of the tube was held 0.1 inch above the surface of
water contained in a vessel at room temperature and the melt was
ejected into the water upon applying 6 psi of gas pressure to the
tube. A continuous, smooth amorphous wire of round cross-section
with a diameter of about 0.008 inch was obtained. The glassy
(amorphous) nature of the wire product was confirmed by x-ray
diffraction. The wire has an elastic limit of about 160,000 psi and
a tensile strength of about 230,000 psi which is about one-fiftieth
of the Young's modulus for this glass, a value which approaches the
theoretical strength of this material.
EXAMPLE 26
Pd.sub.77.5 Cu.sub.6 Si.sub.16.5 was melt spun to a wire of uniform
cross section using the process and apparatus described by Kavesh
in the above-noted U.S. application, Ser. No. 306,472, with an
orifice diameter of 0.005 inch and 10.degree.C water as the quench
medium to yield an amorphous product.
EXAMPLE 27
Following the procedure of Example 25, a Ni.sub.47 Fe.sub.30
P.sub.14 B.sub.6 Si.sub.1 Al.sub.2 alloy was melted at
1000.degree.C and ejected from a 0.005 inch hole into brine held at
-20.degree.C to produce a glassy wire whose amorphous character is
confirmed by x-ray diffraction.
EXAMPLE 28
Following the procedure of Example 26, a Fe.sub.76 P.sub.15 C.sub.4
B.sub.1 Si.sub.1 Al.sub.3 alloy was spun to a glassy wire using a
0.005 inch hole and -20.degree.C brine as the quench medium. The
amorphous character of the wire is confirmed by x-ray
diffraction.
EXAMPLE 29
Following the procedure of Example 26, a Ni.sub.40 Pd.sub.40
P.sub.20 alloy was melted at 700.degree.C and melt spun through a
0.005 inch orifice into iced brine at -20.degree.C to give a glassy
wire. the amorphous characterization is confirmed by x-ray
diffraction.
* * * * *