# US 10,119,178 B2 · Titanium alloy with improved properties > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,119,178 B2 - Document ID: US10119178B2 - Status: Granted - Kind: B2 - Application number: 13/349,483 - Filed: 2012-01-12 - Published: 2012-05-03 - Granted: 2018-11-06 - Earliest claimed: 2012-01-12 - Assignees: Titanium Metals Corporation - Applicants: Roger Thomas; Paul Garratt; John Fanning - Inventors: Roger Thomas; Paul Garratt; John Fanning - Web page: https://patentgrep.com/patent/US10119178B2 ## CPC - C22C 14/00: Alloys based on titanium - C22F 1/183: {of titanium or alloys based thereon} - C22C: ALLOYS (treatment of alloys C21D, C22F) - C22F: CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass, C23F17/00) ## Abstract A titanium alloy having high strength, fine grain size, and low cost and a method of manufacturing the same is disclosed. In particular, the inventive alloy offers a strength increase of about 100 MPa over Ti 6-4, with a comparable density and near equivalent ductility. The inventive alloy is particularly useful for a multitude of applications including components of aircraft engines. The Ti alloy comprises, in weight percent, about 6.0 to about 6.7% aluminum, about 1.4 to about 2.0% vanadium, about 1.4 to about 2.0% molybdenum, about 0.20 to about 0.42% silicon, about 0.17 to about 0.23% oxygen, maximum about 0.24% iron, maximum about 0.08% carbon and balance titanium with incidental impurities. ## Claims ### Claim 1 A ballistic titanium alloy consisting of, in weight %, 6.0 to 6.7 aluminum, 1.4 to 2.0 vanadium, 1.4 to 2.0 molybdenum, 0.20 to 0.35 silicon, 0.18 to 0.23 oxygen, 0.16 to 0.24 iron, 0.02 to 0.06 carbon, and balance titanium with incidental impurities; wherein the maximum concentration of any one impurity element present in the titanium alloy is 0.1 wt. % and the combined concentration of all impurities is less than or equal to 0.4 wt. %, the ballistic titanium alloy having a UTS greater than 950 MPa, a tensile yield strength of at least 1,000 MPa, an elongation of at least 10%, a V50 ballistic limit that is at least 80 feet per second greater than a base V50 ballistic limit measured for a T-64 alloy when a 0.616 inch thick plate is tested against a 12.7 mm diameter steel fragment simulating projectile, and wherein a tensile specimen of the ballistic titanium alloy has a reduction of area (RA) of at least 25% of an original cross-sectional area of the tensile specimen after fracture when evaluated using an ASTM E8 standard. ### Claim 2 (depends on 1) The titanium alloy of claim 1 consisting of, in weight %, about 6.3 to about 6.7 aluminum, about 1.5 to about 1.9 vanadium, about 1.5 to about 1.9 molybdenum, about 0.34 to about 0.35 silicon, about 0.18 to about 0.21 oxygen, 0.16 to 0.2 iron, 0.02 to 0.05 carbon, and balance titanium with incidental impurities. ### Claim 3 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the aluminum is about 6.5. ### Claim 4 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the vanadium is about 1.7. ### Claim 5 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the molybdenum is about 1.7. ### Claim 6 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the silicon is about 0.30. ### Claim 7 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the oxygen is about 0.20. ### Claim 8 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the iron is 0.16. ### Claim 9 (depends on 1) The titanium alloy of claim 1, wherein the weight % of the carbon is about 0.03. ### Claim 10 (depends on 1) The alloy of claim 1 having a molybdenum equivalence (MOeq) of 2.6 to 4.0, wherein the molybdenum equivalence is defined as: MOeq=MO+0.67V+2.9Fe. ### Claim 11 (depends on 1) The alloy of claim 1 having an aluminum equivalence (Aleq) of 10.6 to about 12.9, wherein the aluminum equivalence is defined as: Aleq=Al+27O. ### Claim 12 (depends on 1) An aviation component comprising the titanium alloy of claim 1. ### Claim 13 (depends on 1) A fan blade comprising the titanium alloy of claim 1. ### Claim 14 (depends on 1) The titanium alloy of claim 1 consisting of, in weight %, about 6.5 aluminum, 1.7 vanadium, 1.7 molybdenum, about 0.35 silicon, 0.20 oxygen, 0.16 iron, 0.03 carbon, and balance titanium with incidental impurities. ### Claim 15 (depends on 1) A method of manufacturing a titanium alloy, comprising: a. providing a the titanium alloy of claim 1; b. performing a first heat treatment of the alloy in (a) to a temperature between 40 and 200 degrees Centigrade above the beta transus temperature and forging to break down the cast structure of the ingot and then cooling the alloy; c. performing a second heat treatment of the alloy in (b) to a temperature between 30 and 100 degrees Centigrade below the beta transus and rolling the alloy to a plate, bar, or billet; and d. annealing the alloy in (c) at a temperature below the beta transus. ### Claim 16 (depends on 15) The method of claim 15, further comprising the step of: reheating the alloy in step (b) to a temperature between 50 and 150 degrees Centigrade above the beta transus temperature to allow recrystallization of the beta phase. ### Claim 17 (depends on 15) The method of claim 15, further comprising the step of: reheating the alloy to a temperature between 30 to 150 degrees Centigrade above the beta transus temperature to allow recrystallization of the beta phase, then forging to a strain of at least 10 percent and water quenched. ### Claim 18 A ballistic titanium alloy consisting of, in weight %, 6.0 to 6.7 aluminum, 1.4 to 2.0 vanadium, 1.4 to 2.0 molybdenum, 0.20 to 0.35 silicon, 0.18 to 0.23 oxygen, 0.16 to 0.24 iron, 0.02 to 0.06 carbon and the balance titanium together with any incidental impurities having UTS of at least 160 ksi, a tensile yield strength of at least 145 ksi, an elongation of at least 10%, a V50 ballistic limit that is at least 60 feet per second greater than a base V50 ballistic limit measured for a T-64 alloy when a 0.616 inch thick plate is tested against a 12.7 mm diameter steel fragment simulating projectile, wherein a tensile specimen of the ballistic titanium alloy has a reduction of area (RA) of at least about 25% of an original cross-sectional area of the tensile specimen after fracture when evaluated using an ASTM E8 standard, and wherein the ballistic titanium alloy is manufactured by a) performing an initial melting step; b) conducting a final melt step by vacuum arc remelting; c) performing an intermediate forging above or below beta transus; d) performing a final forging and rolling the alloy at a temperature below the beta transus; e) performing a solution heat treatment of the titanium alloy; and f) performing annealing or precipitation hardening of the titanium alloy at a temperature below the beta transus. ### Claim 19 A ballistic titanium alloy consisting of, in weight %, 6.0 to 6.7 aluminum, 1.4 to 2.0 vanadium, 1.4 to 2.0 molybdenum, 0.20 to 0.35 silicon, 0.18 to 0.23 oxygen, 0.16 to 0.24 iron, 0.02 to 0.06 carbon and the balance titanium together with any incidental impurities, wherein the ballistic titanium alloy is manufactured by: a) performing an initial melting step; b) conducting a final melt step by vacuum arc remelting; c) performing an intermediate forging above or below beta transus; d) performing a final forging and rolling the alloy at a temperature below the beta transus; e) performing a solution heat treatment of the titanium alloy; f) performing annealing or precipitation hardening of the titanium alloy at a temperature below the beta transus, wherein said ballistic titanium alloy has a UTS of at least 160 ksi, a tensile yield strength of at least 145 ksi, an elongation of at least 10%, and a V50 ballistic limit that is at least 80 feet per second greater than a base V50 ballistic limit measured for a T-64 alloy when a 0.616 inch thick plate is tested against a 12.7 mm diameter steel fragment simulating projectile, and wherein a tensile specimen of said ballistic titanium alloy has a reduction of area (RA) of at least about 25% of an original cross-sectional area of the tensile specimen after fracture when evaluated using ASTM E8 standard. ### Claim 20 A ballistic titanium alloy consisting of, in weight %, 6.0 to 6.7 aluminum, 1.4 to 2.0 vanadium, 1.4 to 2.0 molybdenum, 0.20 to 0.35 silicon, 0.18 to 0.23 oxygen, 0.16 to 0.24 iron, 0.02 to 0.06 carbon, and balance titanium with incidental impurities, wherein the ballistic titanium alloy is manufactured by: i) performing a first heat treatment of the titanium alloy to a temperature between 40 and 200 degrees Centigrade above the beta transus temperature and forging to break down the cast structure of the ingot and then cooling the alloy; ii) performing a second heat treatment of the alloy in (i) to a temperature between 30 and 100 degrees Centigrade below the beta transus and rolling the alloy to a plate, bar, or billet; and iii) annealing the alloy in (ii) at a temperature below the beta transus, wherein the ballistic titanium alloy has a UTS greater than 950 MPa, a tensile yield strength of at least 1,000 MPa, an elongation of at least 10%, a V50 ballistic limit that is at least 80 feet per second greater than a base V50 ballistic limit measured for a T-64 alloy when a 0.616 inch thick plate is tested against a 12.7 mm diameter steel fragment simulating projectile, and wherein a tensile specimen of said ballistic titanium alloy has a reduction of area (RA) of at least 25% of an original cross-sectional area of the tensile specimen after fracture when evaluated using an ASTM E8 standard.