Patent · US Expired

Al-base alloys containing lithium, copper and magnesium and method

US4752343A · kind A · utility

9Cited by
1References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 11, 1985
Grant dateJun 21, 1988
Priority date
Expiry dateMar 11, 2005

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22C21/16
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The present invention relates to Al-base alloys essentially containing Li, Cu and Mg, and having high specific characteristics and a high degree of ductility. Their composition is as follows (% by weight): ______________________________________ Li 1.7 to 2.9 Cu 1.5 to 3.4 ##STR1## Mg 1.2 to 2.7 Fe .ltoreq. 0.20 Si .ltoreq. 0.06 Cr 0 to 0.3 Mn 0 to 1.0 Zr 0 to 0.2 Ti 0 to 0.1 Be 0 to 0.01 Other elements (impurities) each .ltoreq. 0.05 total .ltoreq. 0.15 balance: Al ______________________________________ The heat treatment comprises a homogenization step at about .theta.(.degree.C.)=535-5 (% Mg) which practically dissolves the compounds Al-Cu (Li-Mg); a solution treatment at between .theta.+10.degree. C.; a quenching step; and a tempering step at from 170.degree. to 220.degree. C. for a period ranging from 8 to 48 hours. The mechanical strength and ductility characteristics obtained are equivalent to those of conventional alloys 2000 or 7000.

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