Microstructural evolution and mechanical behavior of additively manufactured tantalum produced by electron beam powder bed fusion

Abstract

Tantalum components were manufactured by electron beam powder bed fusion (EB-PBF) at different line energy densities in this study. It was found that, the relative density, grain size and mechanical properties are significantly influenced by line energy density. Tantalum component with relative density above 99% can be achieved when the linear energy density exceeding 960 J/m. The tantalum manufactured at 1200 J/m has a superior mechanical property with tensile yield strength of 331 MPa and elongation of 31.1%, which is better than that prepared by other conventional methods. The high strength is mainly attributed to the fine grains and dislocation network substructure, while the defect-free microstructure and low content of interstitial oxygen atoms are responsible for the good ductility.