Patent · US Expired

Process for improving the ductility of a product of alloy involving martensitic transformation and use thereof

US4878954A · kind A · utility

4Cited by
4References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1988
Grant dateNov 7, 1989
Priority date
Expiry dateJun 17, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22F1/006
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process is disclosed for improving the ductility of shape-memory alloy products based on Ti-Ni involving martensitic transformation. The process comprises at least one thermal treatment cycle of alternating hot and cold treatment, wherein the first thermal treatment cycle comprises a cold treatment at a temperature both lower than -50.degree. C. and lower than M.sub.s -50.degree. C., where M.sub.s is the temperature at which martensitic transformation of the product begins, and a hot treatment of the product at a temperature of 700.degree. to 900.degree. C. Each optional subsequent thermal treatment cycle comprises a cold treatment of the product at a temperature both lower than -50.degree. C. and lower than M.sub.s -30.degree. C., and a hot treatment of the product at a temperature of 600.degree. to 900.degree. C.

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