US 12,442,064 B2
Method of forming precursor into a Ti alloy article
Paul Michael Needham, Balderstone (GB); and Simon Scott, Balderstone (GB)
Assigned to BAE Systems plc, London (GB)
Appl. No. 17/802,031
Filed by BAE Systems plc, London (GB)
PCT Filed Mar. 11, 2021, PCT No. PCT/GB2021/050608
§ 371(c)(1), (2) Date Aug. 24, 2022,
PCT Pub. No. WO2021/181101, PCT Pub. Date Sep. 16, 2021.
Claims priority of application No. 20275056 (EP), filed on Mar. 11, 2020; and application No. 2003495 (GB), filed on Mar. 11, 2020.
Prior Publication US 2023/0106504 A1, Apr. 6, 2023
Int. Cl. C22F 1/18 (2006.01); C22C 14/00 (2006.01)
CPC C22F 1/183 (2013.01) [C22C 14/00 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method of thermomechanically forming, an article from a precursor thereof, the method comprising:
providing the precursor, comprising an α+β Ti alloy having a beta transus temperature βtransus, wherein the precursor comprising at least a first portion; and
thermomechanically forming the article from the precursor by heating the first portion and deforming the heated first portion by a total true strain ε1,total, wherein the total true strain ε1,total is greater than a predetermined threshold true strain εthreshold,
wherein thermomechanically forming the article from the precursor comprises i iterations of:
(a) heating the first portion to a temperature Ti during a time ti, wherein the temperature Ti is at most the beta transus temperature βtransus;
(b) deforming the heated first portion by a true strain ε1,i, wherein the true strain ε1,i is at most the predetermined threshold true strain εthreshold, and
(c) repeating steps (a) and (b) until the cumulative true strain ε1,cumulative=Σiε1,i is the total true strain ε1,total, wherein i is a natural number greater than or equal to 2,
wherein the time ti is in a range from 0.5 hours to 12 hours when i is equal to 1,
wherein the time ti is in a range from 0.25 hours to 4 hours when i is greater than or equal to 2, and
wherein the predetermined threshold true strain εthreshold is in a range from 0.5 to 0.85.