Microstructural and property evolution of Ti6Al4V powders with the number of usage in additive manufacturing by electron beam melting.

The influence of reused times on the characteristics and properties of Ti6Al4V (TC4) powder and resulting bulk materials were systematically investigated in additive manufacturing by electron beam melting (EBM). Optical microscope, X-ray diffraction and nano-indentation were used to characterize the powders. Optical microscope results indicated that the microstructure evolved from non-equilibrium to equilibrium state of α and β phase with increasing reuse times. The micro-hardness and Young’s modulus of reused powders were enhanced with the increase of reuse times. The tensile properties of bulk final product fabricated from the mixed powders were nearly equal or superior to that prepared by 100% fresh powder. In short, the mixing usage of initial and reused Ti6Al4V powders for additive manufacturing is acceptable. [ABSTRACT FROM AUTHOR]