Creep and strengthening in powder metallurgy SiC-Al composites

The creep behavior of particulate SiC-Al composites and their unreinforced Al matrices that were prepared by powder metallurgy has been investigated under similar experimental conditions. The experimental data, which cover several orders of magnitude of strain rate, are discussed with special emphasis on the following: (a) major similarities and differences in creep characteristics between the composites and their matrices, (b) interpretation of creep behavior in terms of a threshold stress, (c) steady-state deformation processes controlling the creep behavior of the materials, and (d) creep strengthening in the composites and the loss of such strengthening at high strain rates.