High temperature deformation of dispersion strengthened aluminum alloys

Abstract

This paper describes the characteristic features of high temperature deformation in dispersion-strengthened materials. It focusses on "reaction-miled" Aluminum alloysf containing oxide and carbide dispersoids: the microstructure of such alloys has been studied by TEM, and the creep properties have been measured at 573 - 773 K in a fine and coarse-grained condition. Recent micromechanistic models for the effect of small dispersoids on the high temperature creep properties are described. The experimental results are then interpreted in the light of a new model-based constitutive equation and compared with those of other dispsersion-strengthened materials. Requrements for optimum high-temperature performance of such alloys, including an optimized grain structure, are discussed.