Additive Manufacturing of Tungsten-Alloyed Tantalum from Polyhedral Shaped Powder Blends

Tantalum and tungsten are completely soluble in each other and are used in applications in the combined form of so-called tantaloys. They provide high melting points (Ta: 3017 °C, W: 3410 °C) and excellent corrosion resistance while maintaining high ductility for W contents up to 7.5 wt%. Providing good resistance to hydrogen embrittlement, Ta-W alloys are attractive candidates for applications in fusion reactors. This study demonstrated the feasibility of producing chemically homogeneous bulk material with fine grained microstructure from non-spherical powder blends with up to 7.5% tungsten using laser powder bed fusion (PBF-L/M). It is observed that cracking remains a challenge, especially with the increase in tungsten content. The effect of rapid solidification on the microhardness of up to 385 HV0.1 for 7.5% W is discussed. It provides initial indications of the possibility of achieving higher strengths and paves the way for further alloy development with regard to the additive manufacturing of this alloy family.