Room-temperature tensile strength and thermal shock behavior of spark plasma sintered W-K-TiC alloys

Abstract

W-K-TiC alloys with different titanium carbide concentrations (0.05, 0.1, 0.25, 0.5, 1, 2) wt.% were fabricated through Mechanical Alloying and Spark Plasma Sintering. The effects of the addition of nano-scaled TiC particles on the relative density, Vickers micro-hardness, microstructure, crystal information, thermal shock resistance, and tensile strength were investigated. It is revealed that the doped TiC nano-particles located at the grain boundaries. The relative density and Vickers micro-hardness of W-K-TiC alloys was enhanced with TiC addition and the highest Vickers micro-hardness is 731.55. As the TiC addition increased from 0.05 to 2 wt%, the room-temperature tensile strength raised from 141 to 353 MPa. The grain size of the W-K-TiC alloys decreased sharply from 2.56 μm to 330 nm with the enhanced TiC doping. The resistance to thermal shock damage of W-K-TiC alloys was improved slightly with the increased TiC addition. Keywords: Potassium-doped tungsten, Titanium carbide, Spark plasma sintering, Tensile strength, Thermal shock