Patent · US Expired

Process for the thermal treatment of thick products made of copper-containing aluminum alloys of the 7000 series

US4200476A · kind A · utility

15Cited by
0References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 20, 1978
Grant dateApr 29, 1980
Priority date
Expiry dateNov 20, 1998

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22F1/053
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process for the thermal treatment of a relatively thick product made of a copper-containing aluminum alloy of the 7000 series, the invention involving a solution heat treatment, quenching and tempering in three steps: PA1 (1) preliminary tempering at between 100.degree. and 150.degree. C. for five minutes to 24 hours; PA1 (2) intermediate tempering; and, PA1 (3) final tempering for 2 to 48 hours at between 100.degree. and 160.degree. C. The intermediate tempering step comprises a rapid rise in temperature in the zone at 150.degree. to 190.degree. C. followed by an evolution .theta.(t) above 190.degree. C. for a period T, such that: ##EQU1## is between 1 and 4, K=1.5 except for certain alloys where K=3. T and t are expressed in seconds, .theta.(t) is expressed in .degree.K. and is between 463.degree. and 523.degree. K. The present process provides increased mechanical strength to the product as well as a high resistance to stress corrosion.

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