Microstructural evolution and mechanical behavior of W-Si-C multi-phase composite prepared by arc-melting

In this work, to improve the strain capacity of tungsten, β-SiC was added to form W-Si-C multi-phase composites composed of W, W2C, and W5Si3 using the arc-melting method. The relationship between microstructure and mechanical behavior was investigated, and a microstructural evolution mechanism was proposed. The grain size of the W was refined significantly from 1071.8 to 5.4 µm as the SiC content increased. The micro-hardness (3.67-12.79 GPa) and ultimate compressive strength (UCS) (0.90-2.29 GPa) of the W-Si-C multi-phase composite obviously increased as the β-SiC content increased to 4 wt% due to the grain refinement and segregation of the W2C and W5Si3 at the grain boundaries. The highest strain of UCS (21.9%) was obtained at 1 wt% SiC, which is three times of that of pure W (7.4%) and is a result of the refined W grain size and the potentiation of W5Si3.