Mechanical Properties and Thermal Shock Performance of High-Energy-Rate-Forged W-1%TaC Alloy

Abstract

Tungsten is a metal with a high melting point and thermal conductivity, but its inherent brittleness limits its application in the industry. Dispersion strengthening and plastic deformation are considered to be an effective means to improve the properties of tungsten alloys. In this work, the mechanical properties and thermal shock performance of W-1% TaC alloy prepared by hot pressing followed by high-energy-rate forging (HERFing) and annealing treatment were investigated. The microstructure of the tungsten material was characterized via metallography, scanning electron microscopy and electron backscattering diffraction imaging. The mechanical properties were studied by tensile testing. The thermal shock performance of the HERFed W-TaC was evaluated using an electron beam device. The forged tungsten possessed a disc-shaped grain structure. The forged W-TaC alloy exhibited a good mechanical performance at an elevated temperature, which was different from the response of other tungsten alloys. The HERFing process effectively increased the cracking threshold of W-TaC alloy under electron beam transient thermal load. The lamellar grain structure of the forged tungsten material prevented cracks from propagating deeply into the material.