Spark plasma sintering of W-30Si refractory targets: Microstructure, densification and mechanical properties

W-30Si refractory targets were widely used as gate materials in the field of semiconductor integrated circuits. This work aimed to study the microstructure, densification mechanism, and mechanical properties of W-30Si targets prepared by spark plasma sintering (SPS). The results manifested that the punch displacement and relative density rose as temperatures increased, and the sintering route processed at 1200 °C included four parts. A fully dense target can be obtained at 1200 °C, while part of Si would volatilize at 1220 °C. No significant variation was observed in grain sizes from 1000 to 1200 °C, thus it was believed that the consolidation predominated over this temperature range. The effective stress exponent (n) was generally regarded as a parameter closely related to the densification mechanism. At the initial stage of 1000 to 1200 °C and the late stage of 1000 °C (n < 1), the particle rearrangement had a major influence on the densification. At the late stage of 1050 to 1200 °C (1 < n < 2), the grain boundary diffusion was a significant factor for consolidation, and the activation energy (n = 1.5) was estimated to be 931.40 kJ/mol. Besides, the microhardness rose with increasing temperatures. The present study laid the groundwork for future research on the fabrication of W-30Si targets by SPS.