Causes of liquid phase migration in powdered metal materials during consolidation by self-propagating high-temperature synthesis

The phenomena of liquid phase migration in the combustion of powdered metal pressings are investigated. The onset of a temperature gradient induced by a combustion wave is established as one of the causes of migration. The resulting capillary potential difference in the pores is directed toward the cooler side of the pressing. It is hypothesized that part of the melt (layers adjacent to the walls of the capillary pores) can move toward the hot side. Techniques are proposed for eliminating the negative consequences of liquation of the molten phase under the influence of the temperature gradient in the sintering of manufactured parts by self-propagating high-temperature synthesis.