Accession Number : AD0748361

Title :   Effects of Thermomechanical Treatments on Aluminum Alloys.

Descriptive Note : Final technical rept., 1 Mar 69-1 Jul 71,

Corporate Author : NORTH AMERICAN ROCKWELL CORP LOS ANGELES CALIF LOS ANGELES DIV

Personal Author(s) : Sommer,A. W. ; Paton,N. E. ; Folgner,D. G.

Report Date : FEB 1972

Pagination or Media Count : 99

Abstract : The effects produced by thermomechanical treatments on the mechanical, microstructural, and stress corrosion resistance properties of 2024, 7049, and 7075 aluminum alloys were investigated. These properties are compared with those obtained in the standard commercial tempers. The optimum benefits of thermomechanical processing are obtained when the material has previously been heattreated to its maximum age-hardenable condition. A thermomechanical response is developed with as little as 5 percent mechanical deformation. The uniformity of this plastic strain throughout the entire mass of the material is a critical factor. This mechanical deformation is carried out at a temperature high enough to develop a homogeneous random distribution of dislocations and to stabilize this configuration by precipitation along a portion of their lengths. The optimum temperature for a postdeformation heat treatment to produce the necessary resistance to stress corrosion cracking is just above the Guinier-Preston zone solvus for the hardening phase. (Author)

Descriptors :   (*ALUMINUM ALLOYS, HEAT TREATMENT), MECHANICAL WORKING, DEFORMATION, MECHANICAL PROPERTIES, STRESS CORROSION

Subject Categories : Properties of Metals and Alloys
      Fabrication Metallurgy

Distribution Statement : APPROVED FOR PUBLIC RELEASE