Patent · US Expired

Titanium alloy having enhanced notch toughness and method of producing same

US6190473A · kind A · utility

6Cited by
23References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 12, 1999
Grant dateFeb 20, 2001
Priority date
Expiry dateAug 12, 2019

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22F1/183
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process for treating an alpha-beta titanium alloy to improve cryogenic notch tensile ratio comprises heating the alloy to near or above its beta transus temperature for a sufficient time to dissolve substantially all alpha grains and thus transform the alloy to the beta form, rapidly cooling the alloy from this temperature to induce a martensitic transformation and produce a fine platelet microstructure, isothermally forging the alloy about 50 to 80 percent at about 300.degree. C. below the beta transus temperature to attain a fine equiaxed microstructure such that the largest microstructural unit is about 2-5 .mu.m, and then aging the alloy at a temperature about 25.degree. C. to 75.degree. C. below the beta transus to grow the refined equiaxed microstructure such that the largest microstructural unit is about 5-10 .mu.m. A titanium alpha-beta alloy having enhanced notch toughness comprises titanium, aluminum, and vanadium and is characterized by a microstructure having equiaxed alpha grains whose volume fraction is about 75 to 85 percent, a maximum grain size of the microstructure not exceeding about 10 .mu.m, and with the volume fraction of primary alpha grains not exceeding a…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.