Structure and mechanical behaviour of povvder processed dispersion strengthened copper

Abstract

Aluminium oxide dispersoid strengthened copper grade Glid-Cop Al-15 fine and coarse mesh fractions have been hot consolidated at 1144 K and then cold worked to 31 and 86%. Tensile and stress rupture specimens were tested to investigate the relationships between microstructure and mechanical properties at room and elevated temperatures. Grain and therefore particle aspect ratio is the most critical structural parameter controlling the high-temperature deformation, which is dominated by grain boundary sliding and intergranular fracture. Grain boundary strengthening is also significant at lower temperatures. Thus, increasing the amount of deformation during the thermomechanical processing of powders can result in high aspect ratios and improved high-temperature mechanical properties. Particle size is found not to play a critical role provided that the aspect ratio is high.

MST/332