US3397979A - Process for incorporating aluminum into dispersion-modified metals - Google Patents

Process for incorporating aluminum into dispersion-modified metals Download PDF

Info

Publication number
US3397979A
US3397979A US519442A US51944266A US3397979A US 3397979 A US3397979 A US 3397979A US 519442 A US519442 A US 519442A US 51944266 A US51944266 A US 51944266A US 3397979 A US3397979 A US 3397979A
Authority
US
United States
Prior art keywords
dispersion
aluminum
nickel
modified
powder
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 - Lifetime
Application number
US519442A
Inventor
Richard F Regester
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fansteel Inc
Original Assignee
Fansteel Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fansteel Inc filed Critical Fansteel Inc
Priority to US519442A priority Critical patent/US3397979A/en
Priority to DE19671558629 priority patent/DE1558629A1/en
Priority to GB1075/67A priority patent/GB1100987A/en
Priority to FR90399A priority patent/FR1507661A/en
Application granted granted Critical
Publication of US3397979A publication Critical patent/US3397979A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/007—Alloys based on nickel or cobalt with a light metal (alkali metal Li, Na, K, Rb, Cs; earth alkali metal Be, Mg, Ca, Sr, Ba, Al Ga, Ge, Ti) or B, Si, Zr, Hf, Sc, Y, lanthanides, actinides, as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
    • C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
    • C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
    • C22C32/0026—Matrix based on Ni, Co, Cr or alloys thereof
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
    • C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
    • C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
    • C22C32/0036—Matrix based on Al, Mg, Be or alloys thereof

Definitions

  • iron-group metals is intended to include the metals iron, cobalt and nickel.
  • alloys of iron group metals is intended to include alloys .inwhich one of the-iron-group metals comprises at least 50%-by weight of the alloy. 1
  • alloys comprising-a matrix of nickel and at least one otheralloying metal, in which alloys there is dispersed a refractory oxide, have, in general, been prepared by blending powders of the alloying metal with the dispersion-modified nickel or nickel-base alloy, and there after cnnsolidating and working the 'blendedrnetal powders to effect alloyingand to'produce a consolidated billet to be subsequently further-worked.
  • this method has given reasonably satisfactory results; in other cases a high degree of porosity develops when the compacted powder billet is heat-treated prior to hot or cold working.
  • An object of this invention is to provide a process for producing an alloy comprising aluminum and iron, cobalt or nickel, in which alloy there is present a uniform dispersion of a refractory metal oxide, and which alloy after Working shows substantially no porosity in the finished work-piece.
  • Another object is to produce intermediate metal work-pieces consisting of dispersion-modified nickelaluminum alloys, said intermediate products being suitable for further hot or cold-working steps to produce dispersion-modified aluminum-bearing mill products which exhi'bit little or no porosity due to interdifl'usion. Further objects will appear hereinbelow.
  • the refractory oxides which are useful in the alloys of this invention will be those having free energy of formation (AF at 1000 C.) of at least 104 kilocalories per gram atom of oxygen.
  • free energy of formation AF at 1000 C.
  • a typical group of suitable oxides, and their free energies of formation in kilocalories per gram atom of oxygen are shown in the following table:
  • fine particles of thoria are dispersed in elemental aluminum, and this dispersion-modified aluminum is alloyed with previously prepared dispersion-modified nickel.
  • Example A dispersion-modified nickel powder known commer cially as TD nickel, produced by E. I. du Pont de Nemours and Company, having a particle size of '325 mesh, was blended with high purity (99.95%) aluminum powder and thoria'powder in the proportion of 93.6 wt. percent Ni alloy to 6 wt. percent Al to 0.4 wt. percent ThO
  • the TD nickel powder was made by coprecipitating thoria particles and basic nickel carbonate, calcining the carbonate to hydrous nickel oxide, and reducing this oxide with hydrogen.
  • the powder contained about 2% thoria as uniformly dispersed particles having an average size of about 25 millimicrons.
  • the three powders were blended in a double cone blender for 2 hours and the mixture then placed in a nickel ball mill with nickel balls and milled for approximately 8 hours.
  • the powder mixture thus formed was compacted hydrostatically at 60,000 psi.
  • the green compact was machined and canned in a mild steel container.
  • the canned compact was evacuated to a pressure of 5 microns to remove adsorbed air. During this evacuation, the compact was heated to approximately 200 F. The billet was then heated in hydrogen according to the following schedule:
  • the billet was cooled in an atmosphere of hydrogen.
  • This sintered compact was extruded at a ratio of 8:1 at 1700 F. It was then subjected to a heat treatment at 2200 F. to homogenize it. During this heat treatment, gross porosity developed throughout the billet. The pores developed at the interface between the original TD nickel particles and the original aluminum particle due to interdifiusion of the nickel and aluminum particles. The diameter of the pores resulting from this interdiffusion varied from 1 to 25 microns and many times were interconnected so as to form cracks in the billet.
  • the extruded and heat-treated rod was hot swaged 30% at a temperature of 2000 F., and then was annealed at 2200 F. for two hours and water quenched.
  • This hot-working step tended to make uniform the grain structure, since large grains occurred where the original aluminium particles were located, and fine grains occurred where the original TD nickel particles were located.
  • the annealed product was cold swaged 70% and following this cold-working step, the voids which had appeared in the billet prior to this step appeared to have collapsed and closed as was evidenced by fine dark lines in the microstructure.
  • the billet was heat-treated at 1850 F. for 2 hours.
  • the effect of this heat treatment was to sinter the walls of the collapsed pores so that a metallurgical bond formed between the walls which had defined the void, and porosity in the rod was almost completely eliminated.
  • the ball-milling of the thoria powder, elemental aluminum powder, and dispersion-modified nickel powder results in the embedding of the thoria in the aluminum powder, and this dispersion-modified aluminum powder is concurrently and thoroughly mixed with the particles of diepersion-modified nickel.
  • the thoria be dispersed in the aluminum before the aluminum is alloyed with the dispersion-modified nickel by the steps of compaction, heating, and working; however, the example illustrates only one method by which this dispersion of the thoria in the aluminum can be accomplished, and other procedures can be used.
  • elemental aluminum powder and thoria can be ball-milled in a separate operation, and the resulting dispersion-modified aluminum thoroughly blended with dispersion-modified nickel before compacting, heating, and working to effect complete alloying.
  • dispersion-modified nickel alloy used was that known commercially as TD nickel, it is not intended that the claims be limited to the use of dispersion-modified iron, cobalt or nickel, or their alloys made by any particular process.
  • the invention is conceived broadly to apply to the production of non-porous aluminum-bearing dispersion-modified iron group metals and alloys regardless of the process by which the oxide strengthening-agent is dispersed in the iron, cobalt, or nickel, or alloys; and also regardless of the particular method by which the strengthening refractory-metal oxide is incorporated in the elemental aluminum prior to the alloying step.
  • iron-group metal selected from the group consisting of iron, cobalt, nickel and alloys comprising these, said iron-group metal or alloy having dispersed substantially uniformly therein about from 0.05 to 10% by volume of a particulate metal oxide having a free energy of formation (AF) at 1000 C. of at least 104 kilocalories per gram atom of oxygen and an average particle size in the range of 5 to 100 millimicrons, the improvement which comprises the steps of (1) dispersing in particulate aluminum about from 0.05 to 10% by volume of a particulate metal oxide have a AF at 1000 C.
  • AF free energy of formation

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)

Description

United States Patent 3,397,979 PROCESS FOR KNCORPORATING ALUM INTO DISPERSION-MODIFIED METALS Richard F. Regester, Havertown, Pa., assignor, by mesne assignments, to Fansteel Metallurgical Corporation, a
corporation of New York 'No Drawing. Filed Jan. 10, 1966, Ser. No. 519,442
2 Claims. (Cl. 75206) ABSTRACT OF THE DISCLOSURE Aluminum is alloyed with a dispersion-modified irongroup metal or alloy having dispersed uniformly therein a particulate metal oxide having a free energy of formation (AF) at 1000 C., of at least 104 kilocalories per gram atom of oxygen and an average particle size in the range of 5 to 100 millimicrons. About 0.05 to by volume of a particulate metal oxide having a AP at '1000 C. of at least 104 kilocalories per gram atom of oxygen is dispersed in particulate aluminum. A minor proportion of said oxide-containing aluminum is mixed with a major proportion of particulate dispersion-modified iron-group metal or alloy and the mixture is alloyed.
In describing this invention the term iron-group metals is intended to include the metals iron, cobalt and nickel. The term alloys of iron group metals is intended to include alloys .inwhich one of the-iron-group metals comprises at least 50%-by weight of the alloy. 1
Heretofore, alloys comprising-a matrix of nickel and at least one otheralloying metal, in which alloys there is dispersed a refractory oxide, have, in general, been prepared by blending powders of the alloying metal with the dispersion-modified nickel or nickel-base alloy, and there after cnnsolidating and working the 'blendedrnetal powders to effect alloyingand to'produce a consolidated billet to be subsequently further-worked. Withsome metals, this method has given reasonably satisfactory results; in other cases a high degree of porosity develops when the compacted powder billet is heat-treated prior to hot or cold working. This porosity has been especially evident where nickel-base dispersion-modified metal powders have been combined with powdered aluminum with the object of preparing a dispersion-modified nickel-aluminum alloy metal product. In these particular alloys the high degree of porosity develops due to interdiifusion of nickel and aluminum at different rates. Where aluminum powder has been blended with a dispersion-modified nickel alloy, and the blended powders are compacted and subsequently heattreated for hot or cold working, non-thoriated areas appear in the areas where the original aluminum powder particles were present in the powder mix.
An object of this invention is to provide a process for producing an alloy comprising aluminum and iron, cobalt or nickel, in which alloy there is present a uniform dispersion of a refractory metal oxide, and which alloy after Working shows substantially no porosity in the finished work-piece. Another object is to produce intermediate metal work-pieces consisting of dispersion-modified nickelaluminum alloys, said intermediate products being suitable for further hot or cold-working steps to produce dispersion-modified aluminum-bearing mill products which exhi'bit little or no porosity due to interdifl'usion. Further objects will appear hereinbelow.
Now according to the present invention it has been found that the above-described difliculties of the prior methods for alloying aluminum with dispersion-modified metals of the iron group can be overcome, and non-porous mill products can be produced by powder blending the dispersion-modified iron-group metal or alloy with pow- 3,397,979 Patented Aug. 20, 1968 dered aluminum, if there is dispersed in the aluminum powder prior to or during the powder-blending step, about from 0.05 to 10% by volume of a particulate metal oxide having a AP at 1000 C. of at least 104 kilocalories per gram of oxygen and an average particle size in the range of 5 to millimicrons, compacting the mixture to a compact, sintering the compact, and hot or cold working the sintered compact.
The refractory oxides which are useful in the alloys of this invention will be those having free energy of formation (AF at 1000 C.) of at least 104 kilocalories per gram atom of oxygen. A typical group of suitable oxides, and their free energies of formation in kilocalories per gram atom of oxygen are shown in the following table:
In a preferred embodiment of the invention, fine particles of thoria are dispersed in elemental aluminum, and this dispersion-modified aluminum is alloyed with previously prepared dispersion-modified nickel.
The following example will illustrate the process of this invention:
Example A dispersion-modified nickel powder, known commer cially as TD nickel, produced by E. I. du Pont de Nemours and Company, having a particle size of '325 mesh, was blended with high purity (99.95%) aluminum powder and thoria'powder in the proportion of 93.6 wt. percent Ni alloy to 6 wt. percent Al to 0.4 wt. percent ThO The TD nickel powder was made by coprecipitating thoria particles and basic nickel carbonate, calcining the carbonate to hydrous nickel oxide, and reducing this oxide with hydrogen. The powder contained about 2% thoria as uniformly dispersed particles having an average size of about 25 millimicrons.
The three powders were blended in a double cone blender for 2 hours and the mixture then placed in a nickel ball mill with nickel balls and milled for approximately 8 hours. The powder mixture thus formed was compacted hydrostatically at 60,000 psi. The green compact was machined and canned in a mild steel container.
The canned compact was evacuated to a pressure of 5 microns to remove adsorbed air. During this evacuation, the compact was heated to approximately 200 F. The billet was then heated in hydrogen according to the following schedule:
2 hours at 600 F. 20 hours at 1150 F. 2 hours at 1650" F.
Following this heating, the billet was cooled in an atmosphere of hydrogen.
This sintered compact was extruded at a ratio of 8:1 at 1700 F. It was then subjected to a heat treatment at 2200 F. to homogenize it. During this heat treatment, gross porosity developed throughout the billet. The pores developed at the interface between the original TD nickel particles and the original aluminum particle due to interdifiusion of the nickel and aluminum particles. The diameter of the pores resulting from this interdiffusion varied from 1 to 25 microns and many times were interconnected so as to form cracks in the billet.
The extruded and heat-treated rod was hot swaged 30% at a temperature of 2000 F., and then was annealed at 2200 F. for two hours and water quenched. This hot-working step tended to make uniform the grain structure, since large grains occurred where the original aluminium particles were located, and fine grains occurred where the original TD nickel particles were located.
The annealed product was cold swaged 70% and following this cold-working step, the voids which had appeared in the billet prior to this step appeared to have collapsed and closed as was evidenced by fine dark lines in the microstructure.
The billet was heat-treated at 1850 F. for 2 hours. The effect of this heat treatment was to sinter the walls of the collapsed pores so that a metallurgical bond formed between the walls which had defined the void, and porosity in the rod was almost completely eliminated.
In the process described in the example, the ball-milling of the thoria powder, elemental aluminum powder, and dispersion-modified nickel powder results in the embedding of the thoria in the aluminum powder, and this dispersion-modified aluminum powder is concurrently and thoroughly mixed with the particles of diepersion-modified nickel. It is essential that the thoria be dispersed in the aluminum before the aluminum is alloyed with the dispersion-modified nickel by the steps of compaction, heating, and working; however, the example illustrates only one method by which this dispersion of the thoria in the aluminum can be accomplished, and other procedures can be used. For example, elemental aluminum powder and thoria can be ball-milled in a separate operation, and the resulting dispersion-modified aluminum thoroughly blended with dispersion-modified nickel before compacting, heating, and working to effect complete alloying.
Although in the example the dispersion-modified nickel alloy used was that known commercially as TD nickel, it is not intended that the claims be limited to the use of dispersion-modified iron, cobalt or nickel, or their alloys made by any particular process. The invention is conceived broadly to apply to the production of non-porous aluminum-bearing dispersion-modified iron group metals and alloys regardless of the process by which the oxide strengthening-agent is dispersed in the iron, cobalt, or nickel, or alloys; and also regardless of the particular method by which the strengthening refractory-metal oxide is incorporated in the elemental aluminum prior to the alloying step.
I claim:
1. In a process for alloying with aluminum an irongroup metal selected from the group consisting of iron, cobalt, nickel and alloys comprising these, said iron-group metal or alloy having dispersed substantially uniformly therein about from 0.05 to 10% by volume of a particulate metal oxide having a free energy of formation (AF) at 1000 C. of at least 104 kilocalories per gram atom of oxygen and an average particle size in the range of 5 to 100 millimicrons, the improvement which comprises the steps of (1) dispersing in particulate aluminum about from 0.05 to 10% by volume of a particulate metal oxide have a AF at 1000 C. of at least 104 kilocalories per gram atom of oxygen, (2) mixing a minor proportion of said oxide-containing aluminum with a major proportion of said dispersion-modified iron-group metal or alloy in particulate form, and (3) thereafter alloying the mixture by compacting, sintering and working.
2. A process of claim 1 in which the iron-group metal is nickel, the refractory oxide dispersed therein is thoria, and the oxide dispersed in the aluminum is also thoria.
References Cited UNITED STATES PATENTS 2,755,184 7/1956 Turner et a1. 170 2,973,570 3/1961 Nachturan 29182.5 3,087,234 4/1963 Alexander et a1. 29-182.5 3,150,443 9/1964 Alexander et a1 29-1825 3,180,727 4/ 1965 Alexander et al. 75-170 FOREIGN PATENTS 941,886 11/ 1963 Great Britain.
CARL D. QUARFORTH, Primary Examiner.
R. L. GRUDZIECKI, Assistant Examiner.
US519442A 1966-01-10 1966-01-10 Process for incorporating aluminum into dispersion-modified metals Expired - Lifetime US3397979A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US519442A US3397979A (en) 1966-01-10 1966-01-10 Process for incorporating aluminum into dispersion-modified metals
DE19671558629 DE1558629A1 (en) 1966-01-10 1967-01-04 Process for the production of aluminum-containing dispersion-hardened alloys based on one or more metals of the iron group
GB1075/67A GB1100987A (en) 1966-01-10 1967-01-09 Dispersion modified alloys
FR90399A FR1507661A (en) 1966-01-10 1967-01-09 Process for incorporating aluminum into modified metals and products thus obtained

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US519442A US3397979A (en) 1966-01-10 1966-01-10 Process for incorporating aluminum into dispersion-modified metals

Publications (1)

Publication Number Publication Date
US3397979A true US3397979A (en) 1968-08-20

Family

ID=24068323

Family Applications (1)

Application Number Title Priority Date Filing Date
US519442A Expired - Lifetime US3397979A (en) 1966-01-10 1966-01-10 Process for incorporating aluminum into dispersion-modified metals

Country Status (4)

Country Link
US (1) US3397979A (en)
DE (1) DE1558629A1 (en)
FR (1) FR1507661A (en)
GB (1) GB1100987A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3520675A (en) * 1967-05-05 1970-07-14 Gen Motors Corp Thoria dispersion strengthened nickel aluminide and method of making
JPS4840091U (en) * 1971-09-17 1973-05-19
US3753795A (en) * 1971-08-02 1973-08-21 Westinghouse Electric Corp Spark plug electrode
US5496918A (en) * 1991-09-23 1996-03-05 Alliedsignal Inc. Process for improving the properties of polymers

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2755184A (en) * 1952-05-06 1956-07-17 Thompson Prod Inc Method of making ni3al
US2973570A (en) * 1958-05-13 1961-03-07 John S Nacthman High temperature structural material and method of producing same
US3087234A (en) * 1960-03-14 1963-04-30 Du Pont Iron group metals having submicron particles of refractory oxides uniformly dispersed therein
GB941886A (en) * 1960-06-13 1963-11-13 Du Pont Improvements in or relating to metalliferous compositions
US3150443A (en) * 1959-12-07 1964-09-29 Du Pont Process of incorporating a refractory metal oxide in a metal and product resulting therefrom
US3180727A (en) * 1962-02-20 1965-04-27 Du Pont Composition containing a dispersionhardening phase and a precipitation-hardening phase and process for producing the same

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2755184A (en) * 1952-05-06 1956-07-17 Thompson Prod Inc Method of making ni3al
US2973570A (en) * 1958-05-13 1961-03-07 John S Nacthman High temperature structural material and method of producing same
US3150443A (en) * 1959-12-07 1964-09-29 Du Pont Process of incorporating a refractory metal oxide in a metal and product resulting therefrom
US3087234A (en) * 1960-03-14 1963-04-30 Du Pont Iron group metals having submicron particles of refractory oxides uniformly dispersed therein
GB941886A (en) * 1960-06-13 1963-11-13 Du Pont Improvements in or relating to metalliferous compositions
US3180727A (en) * 1962-02-20 1965-04-27 Du Pont Composition containing a dispersionhardening phase and a precipitation-hardening phase and process for producing the same

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3520675A (en) * 1967-05-05 1970-07-14 Gen Motors Corp Thoria dispersion strengthened nickel aluminide and method of making
US3753795A (en) * 1971-08-02 1973-08-21 Westinghouse Electric Corp Spark plug electrode
JPS4840091U (en) * 1971-09-17 1973-05-19
JPS5322784Y2 (en) * 1971-09-17 1978-06-13
US5496918A (en) * 1991-09-23 1996-03-05 Alliedsignal Inc. Process for improving the properties of polymers

Also Published As

Publication number Publication date
DE1558629A1 (en) 1970-04-23
FR1507661A (en) 1967-12-29
GB1100987A (en) 1968-01-31

Similar Documents

Publication Publication Date Title
US3740210A (en) Mechanically alloyed aluminum aluminum oxide
US3591362A (en) Composite metal powder
US3837930A (en) Method of producing iron-chromium-aluminum alloys with improved high temperature properties
US3778249A (en) Dispersion strengthened electrical heating alloys by powder metallurgy
US3738817A (en) Wrought dispersion strengthened metals by powder metallurgy
US3524744A (en) Nickel base alloys and process for their manufacture
CN104630639B (en) A kind of nano silicon nitride yttrium dispersion strengthening iron-base alloy and preparation method
US4365996A (en) Method of producing a memory alloy
CN108374113A (en) A kind of preparation method of TaTiZrAlSi high-entropy alloys and its powder
US3809545A (en) Superalloys by powder metallurgy
US3223523A (en) Methods for improving pressed properties and characteristics of sintered powder metal compacts
US4518441A (en) Method of producing metal alloys with high modulus of elasticity
US3723109A (en) Extrusion of canned metal powders using graphite follower block
US3874938A (en) Hot working of dispersion-strengthened heat resistant alloys and the product thereof
US3533760A (en) Dispersion strengthened nickel-chromium alloy composition
US3397979A (en) Process for incorporating aluminum into dispersion-modified metals
US3720551A (en) Method for making a dispersion strengthened alloy article
US2840891A (en) High temperature structural material and method of producing same
US2807542A (en) Method of making high density sintered alloys
US3382051A (en) Dispersion-strengthened iron-group metal alloyed with a small amount of zirconium, hafnium or magnesium and process of making
US3737300A (en) Dispersion strengthened titanium alloys
US3700434A (en) Titanium-nickel alloy manufacturing methods
US3009809A (en) Sintering of iron-aluminum base powders
US3458306A (en) Preparation of metals and metal alloys
US3615381A (en) Process for producing dispersion-hardened superalloys by internal oxidation