Dendrite-reinforced titanium-based metal matrix composites

Patent metadata

Field	Value
Publication number	US-11014162-B2
Application number	US-201815991854-A
Country	US
Kind code	B2
Filing date	May 29, 2018
Priority date	May 26, 2017
Publication date	May 25, 2021
Grant date	May 25, 2021

Abstract

Ti-based metal matrix composites, methods of their additive manufacture, and parts manufactured therefrom and thereby are provided. Method include layer-by-layer additive manufacturing for fabricating Ti-based metal matrix composite parts thicker than 0.5 mm, in layers with thickness between 10-1000 micrometers. The parts formed may have one or more of the following properties: a tensile strength greater than 1 GPa, a fracture toughness greater than 40 MPa m1/2, a yield strength divided by the density greater than 200 MPa cm3/g, and a total strain to failure in a tension test greater than 5%.

First claim

The invention claimed is:

1. A method of additively manufacturing a part comprising a metal composite material comprising:
providing an alloy comprising Ti; at least one β-stabilizer, wherein a β-stabilizer is an element selected from the group consisting of Zr, Hf, Ta, Nb, V, Sn, and Mo; and X, wherein X represents one or more additional elements selected from the group consisting of Co, Fe, Ni, Cu, Al, B, Ag, Pd, Au, C, and Si; wherein the atomic % of Ti in the alloy is greater than the amount of any other element in the alloy, wherein the combined amounts of Ti and the at least one β-stabilizer comprise at least 85 atomic % of the alloy; and wherein the alloy does not contain Be;
additively depositing a plurality of molten layers comprising the alloy atop one another;
cooling each layer of the plurality of molten layers prior to depositing a layer atop thereof at a cooling rate such that upon solidification the alloy segregates phases to produce a metal matrix composite comprising a plurality of isolated crystalline dendrites characterized by a dendrite size and a dendrite density dispersed within a continuous crystalline eutectic material matrix; and
repeating depositing and cooling steps to form a metal matrix composite part with a thickness of at least 0.5 mm.

2. The method of claim 1 , wherein the alloy comprises Ti, Zr, at least one additional beta-stabilizer, and X; and wherein the atomic % of the sum of Ti, Zr, and the at least one additional beta-stabilizer comprises between 85 and 98 atomic % of the alloy, and X comprises from 2 and 15 atomic % of the alloy.

3. The method of claim 2 , wherein the at least one additional beta-stabilizer is selected from the group consisting of V, Nb, Ta, and Mo.

4. The method of claim 1 , wherein Ti comprises at least 50 atomic % of the alloy.

5. The method of claim 1 , wherein the alloy comprises Ti, one or both Zr and Hf, at least one additional beta-stabilizer, B, and at least one additional X; wherein the sum of Ti, the one or both Zr and Hf, and the at least one additional beta-stabilizer comprises between 85 and 98 atomic % of the alloy, B comprises between 0.5 and 5 atomic % of the alloy, and X comprises less than 10 atomic % of the alloy.

6. The method of claim 5 , wherein the at least one additional beta-stabilizer is selected from the group consisting of V, Nb, Ta and Mo, and the at least one additional X is selected from the group consisting of Si, Cu, Co, Fe, and Pd.

7. The method of claim 1 , wherein each layer of the plurality of molten layers is characterized by a thickness of between 10-1000 micrometers.

8. The method of claim 1 , wherein the cooling rate is greater than 10 2 K/s.

9. The method of claim 1 , wherein the plurality of isolated crystalline dendrites comprises at least 60% by volume of the solidified alloy.

10. The method of claim 1 , wherein the continuous crystalline eutectic material matrix is characterized by a matrix hardness and the plurality of isolated crystalline dendrites is characterized by a dendrite hardness, and wherein the matrix hardness is at least 5% larger than the dendrite hardness.

11. The method of claim 1 , wherein the metal matrix composite part has at least one property selected from the group consisting of: a tensile strength of greater than 1 GPa, a fracture toughness of greater than 40 MPa m 1/2 , a density of less than 6.0 g/cm 3 , a total strain to failure of greater than 5% in a tension test, and a yield strength divided by the density greater than 200 MPa cm 3 /g.

12. The method of claim 1 , wherein the alloy is characterized by a solidus temperature of less than 1600 Celsius.

13. The method of claim 1 , wherein the dendrite size ranges from 1 to 20 micrometers in diameter.

14. The method of claim 13 , wherein the dendrite size is less than 10 micrometers in diameter.

15. The method of claim 1 , wherein additively depositing further includes heating the alloy to a semi-solid temperature region between the alloy's solidus and liquidus prior or during a layer deposition.

16. The method of claim 1 , wherein the metal matrix composite part is used in a structural application.

17. The method of claim 1 , wherein additively depositing further comprises adjusting deposition parameters including a deposition temperature and or the cooling rate between depositing at least two adjacent layers of the plurality of molten layers, such that the dendrite size or the dendrite density within the at least two adjacent layers differs and a gradient of properties is created within the metal matrix composite part.

18. The method of claim 1 , wherein additively depositing is a process selected from the group consisting of: powder bed fusion, direct energy deposition, laser foil welding, fused filament fabrication, electron beam fabrication, thermal spraying, and liquid deposition.

19. The method of claim 1 , where the alloy comprises Ti, Nb and from 2 to 15 atomic % B.

20. The method of claim 19 , wherein the concentration of B is 5 atomic %.

21. The method of claim 1 , wherein the alloy is selected from the group consisting of Ti 74 V 10 Zr 10 Si 6 , Ti 64 V 10 Zr 20 Si 6 , Ti 71 V 10 Zr 10 Si 6 Al 3 , Ti 74 Nb 10 Zr 10 Si 6 , Ti 74 Ta 10 Zr 10 Si 6 , Ti 75 Cu 7 Ni 6 Sn 2 V 10 , Ti 75 Cu 7 Ni 6 Sn 2 Nb 10 , Ti 75 Cu 7 Ni 6 Sn 2 Ta 10 , (Ti 72 Zr 22 Nb 6 ) 95 Co 5 , (Ti 72 Zr 22 Nb 6 ) 92 Co 5 Al 3 , (Ti 72 Zr 22 Ta 6 ) 95 Co 5 , (Ti 72 Zr 22 Ta 6 ) 92 Co 5 Al 3 , (Ti 72 Zr 22 V 6 ) 95 Co 5 , (Ti 72 Zr 22 V 6 ) 92 Co 5 Al 3 , Ti 90 Nb 5 Cu 5 , Ti 85 Nb 10 Cu 5 , Ti 80 Nb 5 Cu 10 , Ti 80 Nb 10 Cu 10 , Ti 90 Ta 5 Cu 5 , Ti 85 Ta 10 Cu 5 , Ti 80 Ta 5 Cu 10 , Ti 80 Ta 10 Cu 10 , Ti 90 V 5 Cu 5 , Ti 85 V 10 Cu 5 , Ti 80 V 5 Cu 10 , Ti 80 V 10 Cu 10 , Ti 85 V 10 B 5 , Ti 85 Ta 10 B 5 and Ti 85 Nb 10 B 5 , Ti 57 Zr 18 V 12 Cu 10 Al 3 or Ti 62 Zr 18 V 12 Cu 5 Al 3 .

22. The method of claim 1 , wherein the metal matrix composite part is a type of a part selected form the group consisting of: biomedical implant, structural aerospace component, sporting equipment, medical device, and engine component.

23. A method of additively manufacturing a metal composite part comprising:
providing a metal composite material comprising:
an alloy comprising Ti; at least one β-stabilizer, wherein a β-stabilizer is an element selected from the group consisting of Zr, Hf, Ta, Nb, V, Sn, and Mo; and X, wherein X represents one or more additional elements selected from the group consisting of Co, Fe, Ni, Cu, Al, B, Ag, Pd, Au, C, and Si; wherein the atomic % of Ti in the alloy is greater than the amount of any other element in the alloy, wherein the combined amounts of Ti and the at least one β-stabilizer comprise at least 85 atomic % of the alloy; and wherein the alloy does not contain Be; wherein
the alloy is segregated into phases comprising a plurality of isolated crystalline dendrites dispersed within a continuous crystalline eutectic material matrix

additively depositing a plurality of layers comprising the metal composite material atop one another via a cold deposition process selected from the group consisting of: binder jetting, friction stir additive manufacturing, cold spraying, and ultrasonic additive manufacturing to form a metal matrix composite part with a thickness of at least 0.5 mm.

Assignees

• California Inst Of Techn

Inventors

• Hofmann Douglas C

Classifications

• B22F10/38

  to achieve specific product aspects, e.g. surface smoothness, density, porosity or hollow structures · CPC title

• B22F10/25

  Direct deposition of metal particles, e.g. direct metal deposition [DMD] or laser engineered net shaping [LENS] · CPC title

• B22F10/18

  by mixing binder with metal in filament form, e.g. fused filament fabrication [FFF] · CPC title

• B22F10/14

  by jetting of binder onto a bed of metal powder · CPC title

• B22F10/28 Primary

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title