SIZE-DEPENDENT EFFECTS IN LOW-TEMPERATURE SINTERING AND ALLOYING OF NANOPOWDERS

Abstract

Sintering of nanosized powder mixtures occurs at relatively low temperatures and is accompanied by interdiffusion between the powders and low-temperature homogenization or formation of new phases. The kinetics of interdiffusion depends on the grain size of the structure being formed in the powder compacts. We consider size effects of interdiffusion during sintering at sufficiently low temperatures when bulk diffusion is completely frozen and homogenization or formation of other phases occurs due to diffusion-induced motion of grain boundaries. These effects take place both in the mixtures of mutually soluble powder materials and materials that form intermetallic compounds. We analyze mainly the results obtained as development of the studies that were initiated by Professor Yakov Yevseevich Geguzin.