Effect of pulsed current on the microstructure evolution of Cu–Sn intermetallic compounds

The dissolution behaviour between Cu and Sn during spark plasma sintering (SPS) was investigated with emphasis on the intrinsic effect of the applied pulsed current. Metallographic analyses revealed that the phase formation of Cu–Sn intermetallics was significantly influenced by the applied pulsed current as a series of phase evolutions along the sintering temperature occurred: Cu6Sn5 + Sn → Cu6Sn5 + Cu3Sn → Cu3Sn. The evolution of Cu–Sn intermetallic compounds (IMCs) was analysed by considering the accelerated atomic diffusion and the increased flux of Cu into the IMCs with a pulsed current, which can provide new insights into the basic understanding of the SPS process and promote the development of rapid forming process of IMCs joints for applications at higher temperatures.