Mechanical, electrical and thermal properties at elevated temperature of W-Si-C multi-phase composite prepared by arc-melting

Abstract

In this research, the high-temperature mechanical, electrical and thermal properties of arc-melted W-based composites with a small amount of SiC additives were investigated. The high-temperature mechanical properties of tungsten were enhanced by the presence of the hard ceramic phase (W5Si3 and W2C) and the interaction of dislocations. The ceramic phase also played a role in inhibiting the grain growth at high temperatures. The ultimate compressive strength (UCS) of the W with 1 wt% SiC (S1) was 968.9 MPa at 1273 K, which is three times that of pure W (291.9 MPa) at 1273 K, showing a significant enhancement in high-temperature strength. Both thermal conductivity (κ) and electrical conductivity (σ) decreased with the increasing of SiC addition. With increasing temperature, the σdecreased while the κ increased due to the intrinsic behavior of the ceramic phase in the composites.