Reaction diffusion rate coefficient derivation by isothermal heat treatment in spark plasma sintering system

In spark plasma sintering (SPS) it is widely acknowledged that there are specific physicochemical mechanisms associated with atomic diffusion; however, a reaction diffusion rate coefficient K has yet to be determined. In this work, we derive the K of titanium-copper diffusion couples using isothermal heat treatment of pulsed electric current (PEC), generated in SPS system. Our results show that the derived K for CuTi and Cu4Ti is at least two times higher than the corresponding ones determined under conventional annealing. Accordingly, this work substantiates, for the first time, the argument that PEC accelerates atomic diffusion compared with conventional annealing. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.