Printability and microstructure of Fe doped NiTi shape memory alloy fabricated by laser powder bed fusion

Abstract

NiTiFe shape memory alloy was fabricated by laser powder bed fusion technique via mechanically mixed pure Fe and pre-alloyed NiTi powders. High volumetric energy density related to the low laser power coupled with low scanning speed was benefit for the good printability of NiTiFe alloy, which was attributed to the sufficient fusion of mixed powders. On the basis, the refined columnar grains with weakened texture were obtained. These results confirmed that the additive manufacturing of ternary NiTiFe alloys could be achieved by low-cost mixed powder feedstocks, the printability and microstructure of which could be adjusted by manufacturing process parameters.