Process for forming composites having an intermetallic containing matrix

• US 4,915,903 A
• Filed: 05/05/1988
• Issued: 04/10/1990
• Est. Priority Date: 10/19/1984
• Status: Expired due to Fees

• Current Assignee: Martin Marietta Corporation
• Original Assignee: Martin Marietta Corporation
• Inventors: Nagle, Dennis C., Brupbacher, John M., Christodoulou, Leontios
• Primary Examiner(s): Rutledge, L. Dewayne
• Assistant Examiner(s): Schumaker, David W.
• Application Number:
  US07/190,561
• Time in Patent Office: 705 Days
• Field of Search: 420/129, 420/590, 420/417, 420/418, 420/552, 148/407, 148/415, 148/328
• US Class Current: 420/129
• CPC Class Codes: B22F 3/23 involving a self-propagating high-temperature synthesis or reaction sintering step making cermets by reaction sintering C22C1/051
• CPC Class Codes: B22F 9/14 using electric discharge
• CPC Class Codes: B23K 35/327 comprising refractory compounds, e.g. carbides
• CPC Class Codes: B23K 35/40 Making wire or rods for soldering or welding processes involving a single technical art, see the relevant subclasses, e.g. B05D, B21C
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C22C 1/058 by reaction sintering (i.e. gasless reaction starting from a mixture of solid metal compounds)
• CPC Class Codes: C22C 1/10 Alloys containing non-metals C22C1/05, C22C1/08 take precedence
• CPC Class Codes: C22C 1/1015 by preparing or treating a non-metallic additive preform
• CPC Class Codes: C22C 1/1036 starting from a melt
• CPC Class Codes: C22C 1/1047 by mixing and casting liquid metal matrix composites
• CPC Class Codes: C22C 1/1052 by mixing and casting metal matrix composites with reaction
• CPC Class Codes: C22C 1/1068 Making hard metals based on borides, carbides, nitrides, oxides or silicides
• CPC Class Codes: C22C 29/00 Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides C22C26/00 takes precedence
• CPC Class Codes: C22C 32/00 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
• CPC Class Codes: C22C 32/0078 only silicides
• CPC Class Codes: C22C 47/06 by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element
• CPC Class Codes: C22C 47/08 by contacting the fibres or filaments with molten metal, e.g. by infiltrating the fibres or filaments placed in a mould C22C47/16 takes precedence
• CPC Class Codes: C22C 49/00 Alloys containing metallic or non-metallic fibres or filaments
• CPC Class Codes: C22C 49/14 characterised by the fibres or filaments
• CPC Class Codes: Y10T 428/12486 Laterally noncoextensive components [e.g., embedded, etc.]

Abstract

A method is taught for the formation of intermetallic-second phase composite materials. The method involves the formation of a first metal-second phase composite comprising a relatively high loading of discrete, second phase particles distributed throughout a metal matrix, dilution of the first composite into an additional amount of metal to form a second composite comprising a lower loading of second phase particles within an intermediate metal matrix, and introduction of the second composite into another metal which is reactive with the intermediate metal matrix of the composite to form an intermetallic. A final intermetallic-second phase composite is thereby formed comprising a dispersion of discrete second phase particles throughout a final intermetallic matrix. The final intermetallic matrix may comprise a wide variety of intermetallic materials, with particular emphasis drawn to the aluminides and silicides. Exemplary intermetallics include Ti₃ Al, TiAl, TiAl₃, Ni₃ Al, NiAl, Nb₃ Al, NbAl₃, Co₃ Al, Zr₃ Al, Fe₃ Al, Ta₂ Al, TaAl₃, Ti₅ Si₃, Nb₅ Si₃, Cr₃ Si, CoSi₂ and Cr₂ Nb. The second phase particulate materials may comprise ceramics, such as a borides, carbides, nitrides, oxides, silicides or sulfides, or may comprise an intermetallic other than the matrix intermetallic. Exemplary second phase particulates include TiB₂, ZrB₂, HfB₂, VB₂, NbB₂, TaB₂, MoB₂, TiC, ZrC, HfC, VC, NbC, TaC, WC, TiN, Ti₅ Si₃, Nb₅ Si₃, ZrSi₂, MoSi₂, and MoS₂.

Claims

1. A method for forming intermetallic-second phase composite materials, the method comprising contacting reactive second phase-forming constituents and a solvent metal at a temperature sufficient to initiate an exothermic reaction of the second phase-forming constituents to thereby form a first composite comprising a dispersion of second phase particles within a solvent metal matrix, introducing the first composite into a host metal to form a second composite comprising a dispersion of the second phase particles within an intermediate metal matrix, introducing the second composite into an intermetallic precursor metal which is reactive with the intermediate metal matrix to form an intermetallic containing matrix, and recovering a final composite comprising an intermetallic containing matrix having second phase particles dispersed therein.

2. A method as set forth in claim 1, wherein said solvent metal is selected from the group consisting of aluminum, nickel, copper, titanium, cobalt, iron, platinum, gold, silver, niobium, tantalum, boron, lead, zinc, molybdenum, yttrium, hafnium, tin, tungsten, lithium, magnesium, beryllium, thorium, silicon, chromium, vanadium, zirconium, manganese, scandium, lanthanum, cerium and erbium.

3. A method as set forth in claim 1, wherein said host metal is selected from the group consisting of aluminum, nickel, copper, titanium, cobalt, iron, platinum, gold, silver, niobium, tantalum, boron, lead, zinc, molybdenum, yttrium, hafnium, tin, tungsten, lithium, magnesium, beryllium, thorium, silicon, chromium, vanadium, zirconium, manganese, scandium, lanthanum, cerium and erbium.

4. A method as set forth in claim 1, wherein said intermetallic precursor metal is selected from the group consisting of aluminum, nickel, copper, titanium, cobalt, iron, platinum, gold, silver, niobium, tantalum, boron, lead, zinc, molybdenum, yttrium, hafnium, tin, tungsten, lithium, magnesium, beryllium, thorium, silicon, chromium, vanadium, zirconium, manganese, scandiu, lanthanum, cerium and erbium.

5. A method as set forth in claim 1, wherein said second phase-forming constituents are selected from the group consisting of aluminum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, iron, cobalt, nickel, copper, silicon, boron, carbon, sulfur, nitrogen, oxygen, thorium, scandium, lanthanum, yttrium, cerium and erbium.

6. A method as set forth in claim 1, wherein the second phase-forming constituents and the solvent metal are provided in the form of elemental powders.

7. A method as set forth in claim 1, wherein at least one of the second phase-forming constituents is provided as an alloy of the solvent metal.

8. A method as set forth in claim 1, wherein at least one of the second phase-forming constituents is provided from a compound.

9. A method as set forth in claim 8, wherein the compound is selected from the group consisting of BN, B₄ C, B₂ O₃, AlB₁₂, Al₄ C₃, AlN, SiC, CuO and Fe₂ O₃.

10. A method as set forth in claim 1, wherein the intermetallic containing matrix comprises an aluminide of titanium, nickel, cobalt or niobium.

11. A method as set forth in claim 1, wherein the intermetallic containing matrix comprises a mixture of intermetallic materials.

12. A method as set forth in claim 1, wherein the intermetallic containing matrix comprises TiAl, Ti₃ Al, or a combination thereof.

13. A method as set forth in claim 1, wherein the intermetallic containing matrix comprises TiAl, TiAl₃ or a combination thereof.

14. A method as set forth in claim 1, wherein said second phase is selected from the group consisting of borides, carbides, nitrides, oxides, silicides and sulfides of at least one transition metal of the fourth to sixth groups of the Periodic Table.

15. A method as set forth in claim 1, wherein plural second phase materials are produced.

16. A method as set forth in claim 1, wherein the second phase particles comprise from about 20 to about 80 volume percent of the first composite.

17. A method as set forth in claim 16, wherein the second phase particles comprise from about 2 to about 60 volume percent of the second composite.

18. A method as set forth in claim 17, wherein the second phase particles comprise from about 1 to about 40 volume percent of the final composite.

19. A method as set forth in claim 18, wherein the size of the second phase particles is from about 0.01 to about 10 microns.

20. A method as set forth in claim 1, wherein the solvent metal is aluminum or an alloy thereof.

21. A method as set forth in claim 20, wherein the host metal is aluminum or an alloy thereof.

22. A method as set forth in claim 21, wherein the intermetallic precursor metal is titanium or an alloy thereof.

23. A method as set forth in claim 22, wherein one of the second phase-forming constituents is selected from the group consisting of boron, carbon, nitrogen, oxygen and silicon, and at least one other second phase-forming constituent is selected from the group consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten.

24. A method as set forth in claim 1, wherein an additional amount of the solvent metal is introduced along with the second composite into the intermetallic precursor metal.

25. A method as set forth in claim 1, wherein an additional amount of the first composite is introduced along with the second composite into the intermetallic precursor metal.

26. A method as set forth in claim 1, wherein metal alloying additions are made during the introduction of the first composite into the host metal.

27. A method as set forth in claim 1, wherein metal alloying additions are made during the introduction of the second composite into the intermetallic precursor metal.

28. A method for forming intermetallic-second phase composite materials, the method comprising the steps of:

(a) introducing a first composite comprising a dispersion of in-situ precipitated second phase particles in a solvent metal matrix into a host metal which combines with the solvent metal matrix to form an intermediate metal matrix, to thereby form a second composite comprising a dispersion of the second phase particles within the intermediate metal matrix;

(b) introducing the second composite into an intermetallic precursor metal which is reactive with the intermediate metal matrix to form an intermetallic; and

(c) recovering a final composite comprising a dispersion of second phase particles within an intermetallic containing matrix.

29. A method for forming intermetallic-second phase composite materials, the method comprising the steps of:

(a) preparing a mixture comprising reactive second phase-forming constituents and at least one solvent metal;

(b) heating the mixture to initiate a reaction of the second phase-forming constituents, thereby forming a first composite comprising a dispersion of second phase particles within a solvent metal matrix;

(c) diluting the first composite in a host metal, thereby forming a second composite comprising a dispersion of the second phase particles within an intermediate metal matrix;

(d) introducing the second composite into an intermetallic precursor metal which is reactive with the intermediate metal matrix to form an intermetallic; and

(e) recovering a final composite comprising a dispersion of second phase particles within an intermetallic containing matrix.

30. A method as set forth in claim 29, wherein the mixture is compressed to form a compact prior to the heating thereof.

31. A method as set forth in claim 30, wherein the heating is achieved by bulk heating the compact.

32. A method as set forth in claim 30, wherein the heating is achieved by igniting a substantially localized portion of the compact.

33. A method as set forth in claim 30, wherein the heating is achieved by adding the compact to a molten bath comprising an additional amount of the solvent metal.

34. A method as set forth in claim 29, wherein the first composite is diluted in the host metal by adding the first composite to a molten bath of the host metal.

35. A method as set forth in claim 29, wherein the first composite is diluted in the host metal by contacting the first composite and the host metal in solid form and then heating to a temperature sufficient to melt the solvent metal matrix of the first composite and the host metal.

36. A method as set forth in claim 35, wherein heating of the first composite and the host metal is achieved by arc melting.

37. A method as set forth in claim 29, wherein the second composite is introduced into the intermetallic precursor metal by adding the second composite to a molten bath of the intermetallic precursor metal.

38. A method as set forth in claim 29, wherein the second composite is introduced into the intermetallic precursor metal by contacting the second composite and the intermetallic precursor metal in solid form and then heating to a temperature sufficient to melt the intermediate metal matrix of the second composite and the host metal.

39. A method as set forth in claim 38, wherein heating of the second composite and the intermetallic precursor metal is achieved by arc melting.

40. A method as set forth in claim 29, wherein the intermetallic containing matrix comprises an aluminide of Ti, Ni, Co, Nb, Zr, Fe, Mo, V, or Ta.

41. A method as set forth in claim 29, wherein the intermetallic containing matrix comprises a silicide of Ti, Cr, Co, Ni, V, or Nb.

42. A method as set forth in claim 29, wherein the intermetallic containing matrix comprises at least one intermetallic selected from the group consisting of Ti₃ Al, TiAl, TiAl₃, Ni₃ Al, NiAl, Nb₃ Al, NbAl₃, Co₃ Al, ZrAl₃, ZrAl₂, Zr₂ Al₃, Zr₄ Al₃, Zr₃ Al₂, Zr₃ Al, Fe₃ Al, Ta₂ Al, TaAl₃, Mo₃ Al, MoAl₂, VAl₃, VAl, Ti₅ Si₃, Nb₅ Si₃, Cr₃ Si, Cr₂ Si, V₅ Si₃, Ni₃ Si, CoSi₂ and Cr₂ Nb.

43. A method as set forth in claim 29, wherein said second phase is selected from the group consisting of borides, carbides, nitrides, oxides, silicides and sulfides of at least one transition metal of the fourth to sixth groups of the Periodic Table.

44. A method as set forth in claim 29, wherein said second phase is selected from the group consisting of TiB₂, ZrB₂, HfB₂, VB₂, NbB₂, TaB₂, MoB₂, TiC, ZrC, HfC, VC, NbC, TaC, WC, TiN, Ti₅ Si₃, Nb₅ Si₃, ZrSi₂, MoSi₂, MoS₂, and combinations thereof.

45. A method as set forth in claim 29, wherein said second phase comprises a complex compound selected from the group consisting of borides, carbides, or nitrides of at least two transition metals of the fourth to sixth groups of the Periodic Table.

46. A method as set forth in claim 29, wherein said second phase particles comprise from about 1 to about 40 volume percent of the final composite.

47. A method as set forth in claim 29, wherein the size of the second phase particles is from about 0.01 to about 10 microns.

48. A method as set forth in claim 29, wherein the intermetallic containing matrix has a grain size of less than about 200 microns.

49. A method as set forth in claim 29, wherein the intermetallic containing matrix has a grain size of less than about 40 microns.

50. A method as set forth in claim 29, wherein the second phase comprises TiB₂ and the intermetallic containing matrix comprises Ti-45Al.

51. A method as set forth in claim 29, wherein the second phase comprises TiC and the intermetallic containing matrix comprises Ti-45Al.