Investigating the Microstructure and High-temperature Mechanical Properties of Additively Manufactured W-Re Alloys

Tungsten (W) and W alloys are crucial for high-temperature structural applications due to their impressive properties, including high melting temperature, thermal conductivity, density, strength, and low sputtering yield. However, pure W is extremely brittle at room and low temperatures, limiting its use in applications requiring a cold start. The addition of rhenium (Re) has been shown to significantly reduce the ductile-to-brittle transition temperature, making W-Re alloys considerably more workable than pure W. Despite this improvement, high-temperature characterization remains largely unexplored. In this study, we use laser-powder bed fusion to develop processing parameters for W-Re alloys, such as W-7Re and W-25Re, and investigate their microstructure-property relationships. Post-processing hot isostatic pressing (HIP) is employed to mitigate as-built microcracking, and the tensile properties are measured from room temperature to 2000ºC. Moreover, detailed electron microscopy is ongoing to elucidate the influence of HIP on cracking, recrystallization, and the mechanical response.