Abstract:The main problem of SLM additive preparation of thermoelectric material Cu2Se is that Se element is easy to burn under the action of high energy density heat source of laser. At present, there is no commercially available Cu2Se powder for 3d printing, and no scholars have used SLM to prepare medium temperature thermoelectric material Cu2Se. In this study, laser-induced high-temperature self-propagating reaction + ball milling method was used to prepare Cu2Se powder with good fluidity for SLM additive manufacturing for the first time. Under the optimized process parameters, Cu2Se thermoelectric material additive parts with smooth surface, good mechanical properties and excellent thermoelectric properties were obtained. The grain growth of Cu2Se bulks prepared by SLM has obvious anisotropy in the horizontal and vertical directions. The grains in the vertical section are mainly slender columnar crystals with a length of about hundreds of microns growing along the deposition direction, and the horizontal section is an equiaxed crystal with a size of about tens of microns. There are nano-scale micropore defects at the grain boundaries on the horizontal section. The ZT values measured in the vertical and horizontal directions at 673 K are 0.74 and 0.33, respectively. The maximum compressive strength along the vertical and horizontal directions is 125.08 MPa and 42.69 MPa, respectively. The average microhardness of the additive is 62.5 HV. The thermoelectric properties of Cu2Se prepared in this study are comparable to those of Cu2Se prepared by traditional methods in the vertical direction, and the mechanical properties are good, indicating that it is feasible to prepare Cu2Se thermoelectric materials by SLM. This study opens up a new way for the preparation of medium temperature thermoelectric materials.