Microstructure and properties of laser direct deposited CuNi17Al3Fe1.5Cr alloy

Thin walls of a copper-base alloy with the nominal composition CuNi17Al3Fe1.5Cr were successfully prepared by laser direct deposition additive manufacturing. The microstructure, as revealed by optical and scanning electron microscopy, indicated that the deposited material was fully dense and with a dendritic microstructure. The dendrites are parallel to the build-up direction, which is also the heat conduction direction during deposition. X-ray diffraction analysis results show that the deposited material is composed of a single phase and a copper-based solid solution. Some precipitate particles of metal silicides were observed in the interdendritic region by scanning electron microscopy. The ultimate tensile strength along the laser scanning direction reaches 735 MPa. The hardness is about Hv(0.1) 300.