Effects of initial punch-die clearance in spark plasma sintering process

Abstract

In recent years the number of publication on SPS has grown exponentially although the process itself is still not completely understood. The SPS process is governed by a complex bulk and contact multiphysics. The contact resistance between SPS system elements is crucial to understand the overall current and temperature distribution. This work is undertaken in order to improve our fundamental understanding on the contact resistance behaviour in the SPS system. The effect of the initial punch-die clearance is experimentally investigated for the first time during SPS heating. The results are given in terms of temperature-time and voltage-time profiles for various clearance values. It is shown that the initial punch-die clearance is a key SPS parameter to be specified when different SPS experiments or apparatus features have to be compared and offers another means to control the temperature gradient along the radius. © 2008 The Japan Institute of Metals.