Post Treatment Process and Selective Laser Sintering Mechanism ofPolymer-Coated Mo Powder

摘要

A novel preparing method of polymer-coated molybdenum powder was presented. A type of multi-componentpolymer-coated molybdenum powder was chosen for selective laser sintering. The effect of the process parameters on thepart's characteristics is investigated. Based on our study for dynamic laser sintering process of polymer-coatedmolybdenum powder, its laser sintering mechanism was reported as follows: at the early stage of laser sintering, theviscous flow is the major mechanism; during the laser sintering, the melting/solidification is the major mechanism.Furthermore, a model corresponding to the mechanism was discussed schematically, which could be used to explain thematerial migrating mode during laser sintering process. The laser sintering experiments of polymer-coated Mo powderwas conducted in the self-developed laser sintering machine, and optimized parameters have been acquired. At last, thepost treatment process of laser sintered parts has been developed and refractory metal parts of Mo/Cu composites aregained. The post treatment process includes debinding, high temperature sintering and melting infiltration, which issintering framework-Mo by high temperature combining with Cu impregnation method. It is found that the mechanicalproperties of parts have been greatly improved after the post treatment process.