CA1155319A - Metallic glass powders from glassy alloys - Google Patents
Metallic glass powders from glassy alloysInfo
- Publication number
- CA1155319A CA1155319A CA000348087A CA348087A CA1155319A CA 1155319 A CA1155319 A CA 1155319A CA 000348087 A CA000348087 A CA 000348087A CA 348087 A CA348087 A CA 348087A CA 1155319 A CA1155319 A CA 1155319A
- Authority
- CA
- Canada
- Prior art keywords
- metallic glass
- glass powder
- annealed
- powder according
- making
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C45/00—Amorphous alloys
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/002—Making metallic powder or suspensions thereof amorphous or microcrystalline
- B22F9/008—Rapid solidification processing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D6/00—Heat treatment of ferrous alloys
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
- B22F2009/041—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by mechanical alloying, e.g. blending, milling
Abstract
ABSTRACT
Metallic glass powder is prepared by heating a solid metallic glass body to a temperature below its glass transition temperature for time sufficient to effect embrittlement, followed by comminution of the embrittled metallic glass body.
Metallic glass powder is prepared by heating a solid metallic glass body to a temperature below its glass transition temperature for time sufficient to effect embrittlement, followed by comminution of the embrittled metallic glass body.
Description
DBSCRIPTION
METALLIC GLASS POWDERS FROM GLASSY ALLOYS
.
BACKGROUND OF THE INVENTION
1. Field of the Invention The invention relates to amorphous metal pow-ders and in particular to amorphous metal powders having the composition of known glass forming alloys.
METALLIC GLASS POWDERS FROM GLASSY ALLOYS
.
BACKGROUND OF THE INVENTION
1. Field of the Invention The invention relates to amorphous metal pow-ders and in particular to amorphous metal powders having the composition of known glass forming alloys.
2. Description of the Prior Art Metallic glasses (amorphous metals), including metallic glasses in powder form have been disclosed by Chen et al. in U.S.P. 3,856,513. They prepared amor-phous alloy powders by flash evaporation. They further disclose that powders of amorphous metal having the particle size ranging from about 0.0004 to 0.01 inch (.001016-.0254 centimeter) can be made by atomizing the molten alloy to droplets of this size and then quenching the droplets in a liquid such as water, refrigerated brine or liquid nitrogen.
A method for making metal flakes suitable for making metal powder for powder metallurgical purposes is disclosed by Lundgren in German Offenlegungsschrift 2,553,131 published August 12, 1976. The process in-volves impinging a jet of molten metal against a rotat-ing flat disc. Relatively thin, brittle and easily shattered, essentially dentrite free metal flakes are obtained with between amorphous and microcrystalline structure, from which a metal powder can be obtained by shattering and grinding, for instance in a ball mill.
There remains a need for methods for making amorphous (glassy) metal powder having good properties .
for use in metallurgical processes.
SUMMARY OF THE INVENTION
In accordance with the invention, a method of pro-ducing metallic glass powder is provided wherein a solidmetallic glass body usually in filamentary form is heated at a temperature within the range from about 250C below its glass transiti~n temperature and up to its glass transition temperature for a time sufficient to effect embrittlement without causing formation of a crystalline phase. The em-brittled metallic glass body is comminuted to powder.
DETAILED DESCRIPTION OF THE INVENTION
Metallic glass alloy powders are prepared according to a process involving first annealing a glassy alloy to an embrittled state and then comminuting the embrittled alloy to a powder. Glassy alloys suitable for use in the invention process are known products and are disclosed, for instance, in Chen and Polk TJ.S.P. 3,856,553 issued December 24, 1974.
These alloys can be rapidly quenched from the melt by known procedures to obtain splats or filament (e.g. sheets, ribbons, tapes, wires, etc.) of amorphous metal. These metallic gla4ses in sheet, ribbon, tape, splat and wire form can be annealed at a temperature below the glass transition tem-perature to effect embrittlement.
Heating the metallic glass body to effect embrit-tlement can be carried out in a suitable annealing furnace.
Such annealing furnaces can be divided into furnaces which operate by a batch process and those operating continuously, and either may be electrically heated or fuel fired. Gas heated crucible or box furnaces are suitable, but the glassy metal charge should be protected from the furnace gases by a gas-tight crucible or retort. Electric furnaces with Nichrome0 or Kanthal resistor elements can be used for temperatures up to 1050C which is high enough for embrittlement of most metallic glasses. Nichrome0 is a nickel based alloy having a nominal composition of 60 Ni, 15 Cr, 25 Fe and 1 Si, while Kanthal0 alloys are iron based alloys containing Cr, Al, Co and C. Tightly sealed boxes or retorts in which the glassy material is surrounded by inert B
packs or protective atmospheres can be heated in bell-type or box-type furnaces. Electric muffle furnaces also require a retort if heated by a Nichrome~ or Kanthal~ wire spiral wound on the refractory muffle. Electric box and muffle furnaces may also be heated by silicon carbide heating elements.
Since these elements burn in air, no gas-tight housing is necessary; but the charge must be contained in a closed retort or box to retain the protective atmosphere or pack.
Continuous furnaces are generally more efficient for the production of embrittled metallic glasses. Several suitable types of horizontal continuous furnaces can be used.
One type is the pusher type which is frequently used with metallic or refractory muffles. Th~ furnace can be heated by gas or electricity, and the metallic glass to be embrittled is placed in rigid trays of cast or fabricated alloy, or of graphite. Either mechanical or hydraulic pusher systems may be used, and the push may be either gradual or sudden.
Problems connected with transport of trays con-taining material to be annealed through the furnace can be reduced considerably if friction of the moving trays is eliminated through the incorporation of rolls in the muffle bed or if a mesh belt conveyor furnace is employed. High capacity roller hearth furnaces have rolls in the heating and cooling zones and permit flexible transport of lightweight trays by individual driving mechanisms. Internal gates may subdivide entrance and cooling chambers from the hot zone and prevent the entering of unwanted gases during the opera-tion. Although the glassy metal must travel through an entire mesh belt conveyor furnace at the same speed, rapid heating of the glass is possible by proper distribution of the heat input. If the furnace is divided into several zones, a large part of the heat can be furnished in the first zone and then stored by the heat capacity of the metallic glass. The charge can be placed directly on the conveyor or can be contained in lightweight D
1 1~5319 trays provided with shields to eliminate excessive side radiation from the heating elements.
Vertical continuous furnaces are also suitable and may be coupled with a cooling chamber. The metallic glass in filamentary form is lowered either in continu-ous form or in crucible containers through the furnace and cooling chamber if one is provided, by means of power driven feeding rolls. Rotation of the metallic glass filament at the same time allows a very uniform heat distribution over the metallic glass. The capacity of a vertical furnace is frequently less than that of other types, but larger furnaces for embrittling of up to one ton (907.2 kg) of metallic glass can be provided.
The vertical furnace is especially suitable for the em-brittlement of continuous metallic glass filaments.
Whether the metallic glass body has acquired asufficient de~gree of brittleness can be tested by bend-ing procedures. Depending upon the thickness of the ribbon employed initially a suitable radius can be selected for bending the embrittled ribbon. If the ribbon fails when bent around an adequately sized radius, the embrittlement process has been carried far enough. The larger the radius of breaking, the better embrittled the material. For ease of subsequent com-minution, materials embrittled according to the presentinvention should fail when bent around a radius of about 0.1 cm and preferably of about 0.5 cm.
The annealing temperature may be within the range of from 250C below the glass transition tempera-ture and up to the glass transition temperature, andpreferably is within the range of from 150C below the glass transition temperature to 50C below the glass transition temperature. Lower embrittling temperatures require longer embrittling times than higher embrittling temperatures for achieving comparable degrees of embrit-t~lement. The annealing time therefore varies depending on temperature, and may range from about 1 minute to 100 hours, and is preferably from about 10 minutes to 10 hours.
In case support means for the ribbon to be embrit-tled are needed, they are made from materials which do not reac:t with the alloy even at the highest annealing temperatures employed. Such materials include alumina, zirconia, magnesia, silica and mixed salts thereof; boron nitride, graphite, tungsten, molybdenum, tantalum, silicon, carbide and the like.
The atmosphere employed for the annealing process depends on the specific alloy composition to be annealed.
Numerous metallic glasses can be anneal embrittled in air without being significantly oxidized, and these are pref-erably embrittled in air for the sake of convenience. Vacuum or inert annealing atmospheres can be provided for those alloys which tend to oxidize under anneal embrittlemtent conditions. When annealing in a vacuum, it should be at least 10 3 torr ~1.33 x 10 1 Pa). Generally, inert atmospheres such as provided by gases like argon, helium, neon and nitrogen, are suitable. Reducing atmospheres can be employed to prevent oxidation of the metallic alloy while being annealed. In case a reducing atmosphere is desired, then hydrogen, ammonia, carbon monoxide and the like are preferred. In case of alloys having a metalloid component, it may be advantageous to establish a partial pressure of that metalloid in the annealing atmosphere, e.g., for phosphide metallic glasses an atmosphere having a partial pressure of phosphorus as provided by phosphine in the atmosphere may be preferred.
In addition, it is possible to integrate the process of casting a glassy alloy and of embrittling it.
This can be done by casting of ribbons on a rotating chill substrate and by reducing the residence time of the ribbon on the substrate, so that the ribbon is made to depart the substrate when cooled just below thé glass transition tem-perature (Tg), and then slowly cooling it below the glass transition temperature out of contact with the chill sub-strate for thereby anneal embrittling it. Such embrittled ribbons can be comminuted '~
.L~
in completely analogous fashion to form flake or powder as desired of any desired particle size and particle size distribution.
After the glassy material is embrittled, it is relatively easy to comminute same to flake or fine pow-der, as desired.
Milling equipment suitable for comminution of the embrittled metallic glass includes rod mills, ball mills, impact millsr disc mills, stamps, crushers, rolls and the like. To minimize contamination of the powder, the wearing parts of such equipment are desirably pro-vided with hard and durable facings. Undue heating and ductilization of the powder may be prevented by water cooling of the grinding surfaces. If desired, the com-minution process may be performed under a protective atmosphere or in vacuum to prevent air from affecting the powder. Protective atmospheres can be inert, such as provided by nitrogen, helium, argon, neon and the like, or reducing such as provided by hydrogen.
One type of mill suitable for the comminution of embrittled metallic glass powders is the conventional hammer mill having impact hammers pivotably mounted on a rotating disc. Disintegration of the metallic glass is effected by the large impact forces created by the very high velocity of the rotating disc. Another example of a suitable type of mill is the fluid energy mill.
Ball mills are preferred for use in the com-minuting step inter alia because the resultant product has relatively close particle size distribution.
Following comminution the powder may be screened, for instance, through a 100 mesh screen, if desired, to remove oversize particles. The powder can be further separated into desired particle size frac-tions; for example, into 325 mesh powder and powder of particle size between 100 mesh and 325 mesh. The weight distribution of the particle size fractions of anneal embrittled, ball milled glassy alloy powder Fe65Mol5B20 (atomic percent) was determined for different ball milling times. After milling for 1/2 hour the average part-icle size was about 100 micrometers. After milling for 2 hours the average particle size was reduced to about 80 micrometers. The sample size employed was 100 grams of mat:erial. The diameter of the mill vessel was 10 cm and the length of the mill was 20 cm. The inner surface of the vessel consisted of high density alumina and the ball mill was rotated at 60 r/min. The balls in the mill were made of hiyh density alumina and had a diameter of 1.25 cm.
The powder prepared according to the present invention in general does not exhibit sharp edges with notches as typically found in glassy metallic powders prepared according to the process involving chill casting of an atomized liquid. A particular advantage of a powder with le.ss rough edges is that the particles can slide against each other and as a result can be compacted to higher density at equivalent pressure compared with an analogous chill cast atomized alloy. A compact of higher density is often a more desirable starting material for powder metallurgical appli-cations. The metallic glass powder of the present invention is useful for powder metallurgical applications.
A metallic glass is an alloy product of fusion which has been cooled to a rigid condition without crystal-lization. Such metallic glasses in general have at least some of the following properties: high hardness and resis-tance to scratching, great smoothness of a glassy surface,dimensional and shape stability, mechanical stiffness, strength and ductility and a relatively high electrical resistance compared with related metals and alloys and a diffuse X-ray diffraction pattern. Powder of metallic glass made according to the invention process may comprise fine powder with part-icle size under D
, D
100 micrometers (approximately 155 mesh U.S. Standard), coarse powder with particle size between 100 micrometers (approx. 155 mesh U.S. Standard) and 1000 micrometers (approx. 18 mesh U.S. Standard) and flake with particle size between 1000 micrometers (approx. 18 mesh U.S. Standard) and 5000 micrometers (approx. 4 mesh U.S. Standard), as well as particles of any other desirable particle si~e (e.g. 2000 micrometers or 10 mesh U.S. Standard), as well as particle size distribution, without limitation. Alloys suitable for use in the invention process disclosed in the invention include those known in the art for the preparation for metallic glasses, such as those disclosed in U.S.P.
A method for making metal flakes suitable for making metal powder for powder metallurgical purposes is disclosed by Lundgren in German Offenlegungsschrift 2,553,131 published August 12, 1976. The process in-volves impinging a jet of molten metal against a rotat-ing flat disc. Relatively thin, brittle and easily shattered, essentially dentrite free metal flakes are obtained with between amorphous and microcrystalline structure, from which a metal powder can be obtained by shattering and grinding, for instance in a ball mill.
There remains a need for methods for making amorphous (glassy) metal powder having good properties .
for use in metallurgical processes.
SUMMARY OF THE INVENTION
In accordance with the invention, a method of pro-ducing metallic glass powder is provided wherein a solidmetallic glass body usually in filamentary form is heated at a temperature within the range from about 250C below its glass transiti~n temperature and up to its glass transition temperature for a time sufficient to effect embrittlement without causing formation of a crystalline phase. The em-brittled metallic glass body is comminuted to powder.
DETAILED DESCRIPTION OF THE INVENTION
Metallic glass alloy powders are prepared according to a process involving first annealing a glassy alloy to an embrittled state and then comminuting the embrittled alloy to a powder. Glassy alloys suitable for use in the invention process are known products and are disclosed, for instance, in Chen and Polk TJ.S.P. 3,856,553 issued December 24, 1974.
These alloys can be rapidly quenched from the melt by known procedures to obtain splats or filament (e.g. sheets, ribbons, tapes, wires, etc.) of amorphous metal. These metallic gla4ses in sheet, ribbon, tape, splat and wire form can be annealed at a temperature below the glass transition tem-perature to effect embrittlement.
Heating the metallic glass body to effect embrit-tlement can be carried out in a suitable annealing furnace.
Such annealing furnaces can be divided into furnaces which operate by a batch process and those operating continuously, and either may be electrically heated or fuel fired. Gas heated crucible or box furnaces are suitable, but the glassy metal charge should be protected from the furnace gases by a gas-tight crucible or retort. Electric furnaces with Nichrome0 or Kanthal resistor elements can be used for temperatures up to 1050C which is high enough for embrittlement of most metallic glasses. Nichrome0 is a nickel based alloy having a nominal composition of 60 Ni, 15 Cr, 25 Fe and 1 Si, while Kanthal0 alloys are iron based alloys containing Cr, Al, Co and C. Tightly sealed boxes or retorts in which the glassy material is surrounded by inert B
packs or protective atmospheres can be heated in bell-type or box-type furnaces. Electric muffle furnaces also require a retort if heated by a Nichrome~ or Kanthal~ wire spiral wound on the refractory muffle. Electric box and muffle furnaces may also be heated by silicon carbide heating elements.
Since these elements burn in air, no gas-tight housing is necessary; but the charge must be contained in a closed retort or box to retain the protective atmosphere or pack.
Continuous furnaces are generally more efficient for the production of embrittled metallic glasses. Several suitable types of horizontal continuous furnaces can be used.
One type is the pusher type which is frequently used with metallic or refractory muffles. Th~ furnace can be heated by gas or electricity, and the metallic glass to be embrittled is placed in rigid trays of cast or fabricated alloy, or of graphite. Either mechanical or hydraulic pusher systems may be used, and the push may be either gradual or sudden.
Problems connected with transport of trays con-taining material to be annealed through the furnace can be reduced considerably if friction of the moving trays is eliminated through the incorporation of rolls in the muffle bed or if a mesh belt conveyor furnace is employed. High capacity roller hearth furnaces have rolls in the heating and cooling zones and permit flexible transport of lightweight trays by individual driving mechanisms. Internal gates may subdivide entrance and cooling chambers from the hot zone and prevent the entering of unwanted gases during the opera-tion. Although the glassy metal must travel through an entire mesh belt conveyor furnace at the same speed, rapid heating of the glass is possible by proper distribution of the heat input. If the furnace is divided into several zones, a large part of the heat can be furnished in the first zone and then stored by the heat capacity of the metallic glass. The charge can be placed directly on the conveyor or can be contained in lightweight D
1 1~5319 trays provided with shields to eliminate excessive side radiation from the heating elements.
Vertical continuous furnaces are also suitable and may be coupled with a cooling chamber. The metallic glass in filamentary form is lowered either in continu-ous form or in crucible containers through the furnace and cooling chamber if one is provided, by means of power driven feeding rolls. Rotation of the metallic glass filament at the same time allows a very uniform heat distribution over the metallic glass. The capacity of a vertical furnace is frequently less than that of other types, but larger furnaces for embrittling of up to one ton (907.2 kg) of metallic glass can be provided.
The vertical furnace is especially suitable for the em-brittlement of continuous metallic glass filaments.
Whether the metallic glass body has acquired asufficient de~gree of brittleness can be tested by bend-ing procedures. Depending upon the thickness of the ribbon employed initially a suitable radius can be selected for bending the embrittled ribbon. If the ribbon fails when bent around an adequately sized radius, the embrittlement process has been carried far enough. The larger the radius of breaking, the better embrittled the material. For ease of subsequent com-minution, materials embrittled according to the presentinvention should fail when bent around a radius of about 0.1 cm and preferably of about 0.5 cm.
The annealing temperature may be within the range of from 250C below the glass transition tempera-ture and up to the glass transition temperature, andpreferably is within the range of from 150C below the glass transition temperature to 50C below the glass transition temperature. Lower embrittling temperatures require longer embrittling times than higher embrittling temperatures for achieving comparable degrees of embrit-t~lement. The annealing time therefore varies depending on temperature, and may range from about 1 minute to 100 hours, and is preferably from about 10 minutes to 10 hours.
In case support means for the ribbon to be embrit-tled are needed, they are made from materials which do not reac:t with the alloy even at the highest annealing temperatures employed. Such materials include alumina, zirconia, magnesia, silica and mixed salts thereof; boron nitride, graphite, tungsten, molybdenum, tantalum, silicon, carbide and the like.
The atmosphere employed for the annealing process depends on the specific alloy composition to be annealed.
Numerous metallic glasses can be anneal embrittled in air without being significantly oxidized, and these are pref-erably embrittled in air for the sake of convenience. Vacuum or inert annealing atmospheres can be provided for those alloys which tend to oxidize under anneal embrittlemtent conditions. When annealing in a vacuum, it should be at least 10 3 torr ~1.33 x 10 1 Pa). Generally, inert atmospheres such as provided by gases like argon, helium, neon and nitrogen, are suitable. Reducing atmospheres can be employed to prevent oxidation of the metallic alloy while being annealed. In case a reducing atmosphere is desired, then hydrogen, ammonia, carbon monoxide and the like are preferred. In case of alloys having a metalloid component, it may be advantageous to establish a partial pressure of that metalloid in the annealing atmosphere, e.g., for phosphide metallic glasses an atmosphere having a partial pressure of phosphorus as provided by phosphine in the atmosphere may be preferred.
In addition, it is possible to integrate the process of casting a glassy alloy and of embrittling it.
This can be done by casting of ribbons on a rotating chill substrate and by reducing the residence time of the ribbon on the substrate, so that the ribbon is made to depart the substrate when cooled just below thé glass transition tem-perature (Tg), and then slowly cooling it below the glass transition temperature out of contact with the chill sub-strate for thereby anneal embrittling it. Such embrittled ribbons can be comminuted '~
.L~
in completely analogous fashion to form flake or powder as desired of any desired particle size and particle size distribution.
After the glassy material is embrittled, it is relatively easy to comminute same to flake or fine pow-der, as desired.
Milling equipment suitable for comminution of the embrittled metallic glass includes rod mills, ball mills, impact millsr disc mills, stamps, crushers, rolls and the like. To minimize contamination of the powder, the wearing parts of such equipment are desirably pro-vided with hard and durable facings. Undue heating and ductilization of the powder may be prevented by water cooling of the grinding surfaces. If desired, the com-minution process may be performed under a protective atmosphere or in vacuum to prevent air from affecting the powder. Protective atmospheres can be inert, such as provided by nitrogen, helium, argon, neon and the like, or reducing such as provided by hydrogen.
One type of mill suitable for the comminution of embrittled metallic glass powders is the conventional hammer mill having impact hammers pivotably mounted on a rotating disc. Disintegration of the metallic glass is effected by the large impact forces created by the very high velocity of the rotating disc. Another example of a suitable type of mill is the fluid energy mill.
Ball mills are preferred for use in the com-minuting step inter alia because the resultant product has relatively close particle size distribution.
Following comminution the powder may be screened, for instance, through a 100 mesh screen, if desired, to remove oversize particles. The powder can be further separated into desired particle size frac-tions; for example, into 325 mesh powder and powder of particle size between 100 mesh and 325 mesh. The weight distribution of the particle size fractions of anneal embrittled, ball milled glassy alloy powder Fe65Mol5B20 (atomic percent) was determined for different ball milling times. After milling for 1/2 hour the average part-icle size was about 100 micrometers. After milling for 2 hours the average particle size was reduced to about 80 micrometers. The sample size employed was 100 grams of mat:erial. The diameter of the mill vessel was 10 cm and the length of the mill was 20 cm. The inner surface of the vessel consisted of high density alumina and the ball mill was rotated at 60 r/min. The balls in the mill were made of hiyh density alumina and had a diameter of 1.25 cm.
The powder prepared according to the present invention in general does not exhibit sharp edges with notches as typically found in glassy metallic powders prepared according to the process involving chill casting of an atomized liquid. A particular advantage of a powder with le.ss rough edges is that the particles can slide against each other and as a result can be compacted to higher density at equivalent pressure compared with an analogous chill cast atomized alloy. A compact of higher density is often a more desirable starting material for powder metallurgical appli-cations. The metallic glass powder of the present invention is useful for powder metallurgical applications.
A metallic glass is an alloy product of fusion which has been cooled to a rigid condition without crystal-lization. Such metallic glasses in general have at least some of the following properties: high hardness and resis-tance to scratching, great smoothness of a glassy surface,dimensional and shape stability, mechanical stiffness, strength and ductility and a relatively high electrical resistance compared with related metals and alloys and a diffuse X-ray diffraction pattern. Powder of metallic glass made according to the invention process may comprise fine powder with part-icle size under D
, D
100 micrometers (approximately 155 mesh U.S. Standard), coarse powder with particle size between 100 micrometers (approx. 155 mesh U.S. Standard) and 1000 micrometers (approx. 18 mesh U.S. Standard) and flake with particle size between 1000 micrometers (approx. 18 mesh U.S. Standard) and 5000 micrometers (approx. 4 mesh U.S. Standard), as well as particles of any other desirable particle si~e (e.g. 2000 micrometers or 10 mesh U.S. Standard), as well as particle size distribution, without limitation. Alloys suitable for use in the invention process disclosed in the invention include those known in the art for the preparation for metallic glasses, such as those disclosed in U.S.P.
3,856,513; U.S.P. 3,981,722; U.S.P. 3,986,867; U.S.P.
3,989,517 as well as many others. For example, Chen and Polk in U.S.P. 3,856,513 disclose alloys of the composition M YbZ , where M is one of the metals, iron, nickel, cobalt, chromium and vanadium, Y is one of the metalloids, phosphorus, boron and carbon, and Z equals aluminum, silicon, tin, germanium indium, antimony or beryllium, with "a"
equaling 60 to 90 atom percent, "b" equaling 10 to 30 atom percent and "c" equaling 0.1 to 15 atom percent with the proviso that the sum of "a", "b" and "c" equals 100 atom percent. Preferred alloys in this range comprise those where "a" lies in the range of 75 to 80 atom percent, "b" in the range of 9 to 22 atom percent, "c" in the range of 1 to 3 atom percent. Furthermore, they disclose alloys with the formula TiXj, wherein T is a transition metal and X is one of the elements of the groups consisting of phosphorus, boron, carbon, aluminum, silicon, tin, germanium, indium, beryllium and antimony and wherein "i" ranges between 70 and 87 atom percent and "j" ranges between 13 and 30 atom percent.
However, it is pointed out that not every alloy in this range would form a glassy metal alloy.
The examples set forth below further illustrate the present invention and set forth the best mode presently contempleted for its practice.
Example 1 A metallic glass in the form of ribbon of composi-B ~ tion Fe40Ni4opl4B6 (atom percent) having a glass 11553~9 g transition temperature of 400C was annealed at 250~C
for 1 hour. The annealing atmosphere was argon. X-ray diffraction analysis showed that the annealed ribbon remained fully glassy. The resulting ribbon was brit-tle, and was ground in a ball mill under high purityargon atmosphere for 1.5 hours. The ball mill vessel was made of aluminum oxide and the balls were high den-sity aluminum oxide. The resulting particles had a size of between about 25 and 100 micrometers. X-ray diffraction analysis and differential scanning calorimetry revealed that the powder was fully glassy.
Examples 2-8 Metallic glass in ribbon form of composition indicated in Table 1 was annealed in high purity argon atmosphere at temperatures and for times given to effect embrittlement. X-ray diffraction analysis showed that the annealed ribbon remained fully amorphous. The em-brittled ribbon was ground in a ball mill under high purity argon atmosphere for the time indicated in the table. The ball mill vessel was made of alumina oxide and the balls were made of high density alumina oxide.
The resultant ball milled powder had a-fine particle size between about 25 and 125 micrometers, as given in the table, and the powders were found to be noncrystalline by X-ray analysis and differential scanning calorimetry.
Example 9 --Nickel, cobalt and iron base metallic glass alloys containing chromium and molybdenum can be fabri-cated by powder metallurgical techniques into structuralparts with excellent properties desirable for wear and corrosion resistant applications. Such materials will find uses in pumps, extruders, mixers, compressors, valves, bearings and seals especially in the chemical industry.
Metallic glass powders having the composition (atom percent) Ni60cr2oB2o~ Fe65Crl5 20' 50 30220 and Co50Mo30B20 were hot pressed in vacuum of 10 torr (1.33 Pa) for 1/2 hour under 4000 psi (2.76 x 107 Pa) between 800 and 950C into cylindrical compacts. The cylindrical compacts containing crystalline phases up to 100 percent had hardness values ranging between 1150 and 5 1400 kg/mm2. The above compacts were kept immersed in a solution of 5 wt% NaCl in water at room temperature for 720 hours. The samples exhibited no traces of corros ion .
TABLE I
E~anple 2 Exaltple 3 10 COIT~?OSitiOnFe65Crl5B20 Fe50Ni2oMoloB2o [atom peroent]
Thic~ness 0.0015 in. 0.0015 in.
( 0 . 00381 cm) ( 0 . 00381 cm) 15 Annealing 300 350 Ten~erature [ C]
Annealing 1.5 2 Time [hl 20 Milling Time 2 [h]
Milled Power 50-125 75-125 Size [microrneters]
Exan~?le 4 Exanple 5 Conposition45 o20CrlOFe5Mo4B16Fe45NilOco7Molocr8B2o [atom peroentl Thickness Annealing 400 350 Te~erature [C]
Annealing 1 1. 5 Time [hl Milling Time 6 3 [h]
Milled Power 30-100 75-125 Size [micrometers]
TABLE I (Continued) Exalrple 6Exanple 7 Example 8 Col~QosltionFe80B20Fe40Ni40B20Fe65Mol5B20 Thickness 0.0015 in.
(0.00381 cm) Annealing TenQerature 300 350 400 [C]
Annealing Ti ne [h] 2 2 2 Milling Time [h] 6 4 2 Milled Pawer Size [micrometers] 75-125 75-125 25-100
3,989,517 as well as many others. For example, Chen and Polk in U.S.P. 3,856,513 disclose alloys of the composition M YbZ , where M is one of the metals, iron, nickel, cobalt, chromium and vanadium, Y is one of the metalloids, phosphorus, boron and carbon, and Z equals aluminum, silicon, tin, germanium indium, antimony or beryllium, with "a"
equaling 60 to 90 atom percent, "b" equaling 10 to 30 atom percent and "c" equaling 0.1 to 15 atom percent with the proviso that the sum of "a", "b" and "c" equals 100 atom percent. Preferred alloys in this range comprise those where "a" lies in the range of 75 to 80 atom percent, "b" in the range of 9 to 22 atom percent, "c" in the range of 1 to 3 atom percent. Furthermore, they disclose alloys with the formula TiXj, wherein T is a transition metal and X is one of the elements of the groups consisting of phosphorus, boron, carbon, aluminum, silicon, tin, germanium, indium, beryllium and antimony and wherein "i" ranges between 70 and 87 atom percent and "j" ranges between 13 and 30 atom percent.
However, it is pointed out that not every alloy in this range would form a glassy metal alloy.
The examples set forth below further illustrate the present invention and set forth the best mode presently contempleted for its practice.
Example 1 A metallic glass in the form of ribbon of composi-B ~ tion Fe40Ni4opl4B6 (atom percent) having a glass 11553~9 g transition temperature of 400C was annealed at 250~C
for 1 hour. The annealing atmosphere was argon. X-ray diffraction analysis showed that the annealed ribbon remained fully glassy. The resulting ribbon was brit-tle, and was ground in a ball mill under high purityargon atmosphere for 1.5 hours. The ball mill vessel was made of aluminum oxide and the balls were high den-sity aluminum oxide. The resulting particles had a size of between about 25 and 100 micrometers. X-ray diffraction analysis and differential scanning calorimetry revealed that the powder was fully glassy.
Examples 2-8 Metallic glass in ribbon form of composition indicated in Table 1 was annealed in high purity argon atmosphere at temperatures and for times given to effect embrittlement. X-ray diffraction analysis showed that the annealed ribbon remained fully amorphous. The em-brittled ribbon was ground in a ball mill under high purity argon atmosphere for the time indicated in the table. The ball mill vessel was made of alumina oxide and the balls were made of high density alumina oxide.
The resultant ball milled powder had a-fine particle size between about 25 and 125 micrometers, as given in the table, and the powders were found to be noncrystalline by X-ray analysis and differential scanning calorimetry.
Example 9 --Nickel, cobalt and iron base metallic glass alloys containing chromium and molybdenum can be fabri-cated by powder metallurgical techniques into structuralparts with excellent properties desirable for wear and corrosion resistant applications. Such materials will find uses in pumps, extruders, mixers, compressors, valves, bearings and seals especially in the chemical industry.
Metallic glass powders having the composition (atom percent) Ni60cr2oB2o~ Fe65Crl5 20' 50 30220 and Co50Mo30B20 were hot pressed in vacuum of 10 torr (1.33 Pa) for 1/2 hour under 4000 psi (2.76 x 107 Pa) between 800 and 950C into cylindrical compacts. The cylindrical compacts containing crystalline phases up to 100 percent had hardness values ranging between 1150 and 5 1400 kg/mm2. The above compacts were kept immersed in a solution of 5 wt% NaCl in water at room temperature for 720 hours. The samples exhibited no traces of corros ion .
TABLE I
E~anple 2 Exaltple 3 10 COIT~?OSitiOnFe65Crl5B20 Fe50Ni2oMoloB2o [atom peroent]
Thic~ness 0.0015 in. 0.0015 in.
( 0 . 00381 cm) ( 0 . 00381 cm) 15 Annealing 300 350 Ten~erature [ C]
Annealing 1.5 2 Time [hl 20 Milling Time 2 [h]
Milled Power 50-125 75-125 Size [microrneters]
Exan~?le 4 Exanple 5 Conposition45 o20CrlOFe5Mo4B16Fe45NilOco7Molocr8B2o [atom peroentl Thickness Annealing 400 350 Te~erature [C]
Annealing 1 1. 5 Time [hl Milling Time 6 3 [h]
Milled Power 30-100 75-125 Size [micrometers]
TABLE I (Continued) Exalrple 6Exanple 7 Example 8 Col~QosltionFe80B20Fe40Ni40B20Fe65Mol5B20 Thickness 0.0015 in.
(0.00381 cm) Annealing TenQerature 300 350 400 [C]
Annealing Ti ne [h] 2 2 2 Milling Time [h] 6 4 2 Milled Pawer Size [micrometers] 75-125 75-125 25-100
Claims (12)
- I claim:
l. A method for making metallic glass powder com-prising:
annealing a solid metallic glass body at temperature within the range from about 250°C below its glass transition temperature up to its glass transition temperature, for time sufficient to effect embrittlement; and comminuting the em-brittled metallic glass body. - 2. The method for making metallic glass powder according to claim 1 wherein the metallic glass is annealed under a vacuum of at least 10-3 torr (1.33 x 10-1 Pa).
- 3. The method for making metallic glass powder according to claim l wherein the metallic glass body is annealed in an inert atmosphere.
- 4. The method for making metallic glass powder according to claim 3 wherein the inert atmosphere is an argon atmosphere.
- 5. The method for making metallic glass powder according to claim 3 wherein the inert atmosphere is pro-vided by high purity argon.
- 6. The method for making metallic glass powder according to claim 1 wherein the solid metallic glass body is annealed at a temperature of between 50°C and 150°C
below its glass transition temperature. - 7. The method for making metallic glass powder according to claim l wherein the solid metallic glass body is annealed for a time period of less than about two hours.
- 8. The method for making metallic glass powder according to claim 7 wherein the metallic glass body is annealed in an inert atmosphere.
- 9. Metallic glass powder having particle size of less than 4 mesh (U.S. Standard) comprising platelets having thickness of less than 0.1 millimeter, each platelet being of substantially uniform thickness throughout, and each platelet being defined by an irregularly shaped outline resultant from fracture.
- 10. The metallic glass powder of claim 9 hav-ing particle size of less than 10 mesh (U.S. Standard).
- 11. The metallic glass powder of claim 9 wherein said platelets have a substantially uniform thickness throughout of between about 0.02 and about 0.075 millimeter.
- 12. The metallic glass powder of claim 11 having particle size of less than about 10 mesh (U.S.
Standard).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/023,411 US4290808A (en) | 1979-03-23 | 1979-03-23 | Metallic glass powders from glassy alloys |
| US023,411 | 1979-03-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1155319A true CA1155319A (en) | 1983-10-18 |
Family
ID=21814934
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000348087A Expired CA1155319A (en) | 1979-03-23 | 1980-03-21 | Metallic glass powders from glassy alloys |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US4290808A (en) |
| EP (1) | EP0019682B1 (en) |
| JP (2) | JPS60401B2 (en) |
| AT (1) | ATE8589T1 (en) |
| AU (1) | AU531480B2 (en) |
| CA (1) | CA1155319A (en) |
| DE (1) | DE3010506C2 (en) |
Families Citing this family (26)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4365994A (en) | 1979-03-23 | 1982-12-28 | Allied Corporation | Complex boride particle containing alloys |
| US4406700A (en) * | 1979-11-14 | 1983-09-27 | Allied Corporation | Powder produced by embrittling of metallic glassy alloy by hydrogen charging |
| US4381943A (en) * | 1981-07-20 | 1983-05-03 | Allied Corporation | Chemically homogeneous microcrystalline metal powder for coating substrates |
| US4503085A (en) * | 1981-07-22 | 1985-03-05 | Allied Corporation | Amorphous metal powder for coating substrates |
| US4389258A (en) * | 1981-12-28 | 1983-06-21 | Allied Corporation | Method for homogenizing the structure of rapidly solidified microcrystalline metal powders |
| US4650130A (en) * | 1982-01-04 | 1987-03-17 | Allied Corporation | Rapidly solidified powder production system |
| US4473402A (en) * | 1982-01-18 | 1984-09-25 | Ranjan Ray | Fine grained cobalt-chromium alloys containing carbides made by consolidation of amorphous powders |
| US4400212A (en) * | 1982-01-18 | 1983-08-23 | Marko Materials, Inc. | Cobalt-chromium alloys which contain carbon and have been processed by rapid solidification process and method |
| US4379720A (en) * | 1982-03-15 | 1983-04-12 | Marko Materials, Inc. | Nickel-aluminum-boron powders prepared by a rapid solidification process |
| GB2118207A (en) * | 1982-03-31 | 1983-10-26 | Rolls Royce | Method of making a part for a rolling element bearing |
| JPS58197205A (en) * | 1982-05-10 | 1983-11-16 | Asahi Chem Ind Co Ltd | Novel flaky metallic powder and its manufacture |
| US4606977A (en) * | 1983-02-07 | 1986-08-19 | Allied Corporation | Amorphous metal hardfacing coatings |
| US4545955A (en) * | 1983-05-18 | 1985-10-08 | James Dickson | Can for containing material for consolidation into widgets and method of using the same |
| DE3422281A1 (en) * | 1983-06-20 | 1984-12-20 | Allied Corp., Morristown, N.J. | Process for manufacturing mouldings from magnetic metal alloys, and mouldings thus produced |
| US4621031A (en) * | 1984-11-16 | 1986-11-04 | Dresser Industries, Inc. | Composite material bonded by an amorphous metal, and preparation thereof |
| JPS6353204A (en) * | 1986-08-23 | 1988-03-07 | Nippon Steel Corp | Production of amorphous alloy powder |
| JPS63176435A (en) * | 1987-01-13 | 1988-07-20 | Mitsubishi Heavy Ind Ltd | Strip floater |
| DE3741290C2 (en) * | 1987-12-05 | 1993-09-30 | Geesthacht Gkss Forschung | Application of a process for the treatment of glass-like alloys |
| JPH04130198U (en) * | 1991-05-22 | 1992-11-30 | 株式会社ジエイエスピー | Conveying device for sheet molded products |
| US6258185B1 (en) | 1999-05-25 | 2001-07-10 | Bechtel Bwxt Idaho, Llc | Methods of forming steel |
| US6689234B2 (en) * | 2000-11-09 | 2004-02-10 | Bechtel Bwxt Idaho, Llc | Method of producing metallic materials |
| US6797080B2 (en) * | 2001-07-09 | 2004-09-28 | Showa Denko Kabushiki Kaisha | Method for producing spraying material |
| JP2003027205A (en) * | 2001-07-09 | 2003-01-29 | Showa Denko Kk | Method for producing thermal spraying material |
| CN1758972A (en) * | 2003-02-11 | 2006-04-12 | 纳米钢公司 | Formation of metallic thermal barrier alloys |
| US7341765B2 (en) * | 2004-01-27 | 2008-03-11 | Battelle Energy Alliance, Llc | Metallic coatings on silicon substrates, and methods of forming metallic coatings on silicon substrates |
| JP4902520B2 (en) * | 2007-12-21 | 2012-03-21 | 株式会社ストロベリーコーポレーション | HINGE DEVICE, SLIDING DEVICE, AND ELECTRONIC DEVICE USING THEM |
Family Cites Families (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE536824C (en) * | 1929-01-31 | 1931-10-27 | Int Standard Electric Corp | Process for the production of finely divided, magnetizable alloys for mass cores, in particular iron-nickel-cobalt alloys |
| US3790407A (en) * | 1970-12-28 | 1974-02-05 | Ibm | Recording media and method of making |
| DE2126687A1 (en) * | 1971-05-28 | 1972-12-07 | Simpson Th | Magnetic materials - with amorphous structures |
| US3856513A (en) * | 1972-12-26 | 1974-12-24 | Allied Chem | Novel amorphous metals and amorphous metal articles |
| US3970254A (en) * | 1974-08-19 | 1976-07-20 | Black Clawson Fibreclaim, Inc. | Method for separating glass from heat resistant materials |
| JPS5151908A (en) * | 1974-11-01 | 1976-05-07 | Fuji Photo Film Co Ltd | |
| US4069045A (en) * | 1974-11-26 | 1978-01-17 | Skf Nova Ab | Metal powder suited for powder metallurgical purposes, and a process for manufacturing the metal powder |
| SE7414810L (en) * | 1974-11-26 | 1976-05-28 | Skf Nova Ab | METAL FLAKE PRODUCT LEMPAD FOR THE MANUFACTURE OF METAL POWDER FOR POWDER METALLURGIC FOR SALE AND METHODS OF MANUFACTURE PRODUCTS |
| US4063942A (en) * | 1974-11-26 | 1977-12-20 | Skf Nova Ab | Metal flake product suited for the production of metal powder for powder metallurgical purposes, and a process for manufacturing the product |
| JPS5194211A (en) * | 1975-02-15 | 1976-08-18 | ||
| US4067732A (en) * | 1975-06-26 | 1978-01-10 | Allied Chemical Corporation | Amorphous alloys which include iron group elements and boron |
| US4052201A (en) * | 1975-06-26 | 1977-10-04 | Allied Chemical Corporation | Amorphous alloys with improved resistance to embrittlement upon heat treatment |
| US4101311A (en) * | 1977-08-01 | 1978-07-18 | Fuji Photo Film Co., Ltd. | Process for producing ferromagnetic metal powder |
| JPS5476469A (en) * | 1977-11-30 | 1979-06-19 | Fukuda Metal Foil Powder | Production of amorphous alloy powder |
| US4158582A (en) * | 1978-04-14 | 1979-06-19 | Westinghouse Electric Corp. | Method of making pressed magnetic core components |
| US4197146A (en) * | 1978-10-24 | 1980-04-08 | General Electric Company | Molded amorphous metal electrical magnetic components |
| DE3503228A1 (en) * | 1985-01-31 | 1986-08-07 | Wiederaufarbeitungsanlage Karlsruhe Betriebsgesellschaft mbH, 7514 Eggenstein-Leopoldshafen | SAMPLING DEVICE |
-
1979
- 1979-03-23 US US06/023,411 patent/US4290808A/en not_active Expired - Lifetime
-
1980
- 1980-01-22 EP EP80100304A patent/EP0019682B1/en not_active Expired
- 1980-01-22 AT AT80100304T patent/ATE8589T1/en active
- 1980-03-19 DE DE3010506A patent/DE3010506C2/en not_active Expired
- 1980-03-19 AU AU56576/80A patent/AU531480B2/en not_active Ceased
- 1980-03-21 CA CA000348087A patent/CA1155319A/en not_active Expired
- 1980-03-21 JP JP55036021A patent/JPS60401B2/en not_active Expired
-
1984
- 1984-06-27 JP JP59132834A patent/JPS6043401A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| DE3010506C2 (en) | 1984-09-27 |
| JPS6043401A (en) | 1985-03-08 |
| ATE8589T1 (en) | 1984-08-15 |
| JPS60401B2 (en) | 1985-01-08 |
| EP0019682A1 (en) | 1980-12-10 |
| JPS6342681B2 (en) | 1988-08-25 |
| AU5657680A (en) | 1980-09-25 |
| DE3010506A1 (en) | 1980-09-25 |
| JPS55128506A (en) | 1980-10-04 |
| AU531480B2 (en) | 1983-08-25 |
| EP0019682B1 (en) | 1984-07-25 |
| US4290808A (en) | 1981-09-22 |
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