A rapid prototyping process of selective laser sintering (SLS) which can be used to refractory metal parts manufacturing is introduced in this text.SLS material of polymer-coated Mo powder is prepared by coating polymer and freezing grinding methods.The laser sintering process has been experimentally researched,and optimized parameters have been acquired.The post treatment process of prototyping parts has been developed,which is sintering framework-Mo by high temperature combining with Cu impregnation method.At last,refractory metal parts of Mo/Cu composites are gained.SEM graph shows that Mo and Cu are close jointed together,and these phases distribute interlocked Mechanical and thermal properties of the material have been tested,concluding tensile strength(470 MPa),elastic modulus(267.8 GPa),elongation(15%),linear expansion(5.5×10-6/K).The technology can be applied to manufacturing fire-resisting parts of weaponry and aerospace arms,as well as conductance and cooling elements used to electronics industry.
Liu Bin,Bai Peikang,Ding Erming College of Material Science and Engineering,North University of China,Taiyuan 030051,China
The density of the SLM forming parts is investigated to determine the good technological parameters of SLM at the same time obtain the dense parts. In the SLM experiment, material used is Fe-Ni metal powder, the good technological parameters of SLM are determined by analyzing the effect of the laser electric current, the laser pulse width, the pulse of laser light frequency, the scan speed, the scan interval, push powder thickness and the scanning way on the single channel scanning, the single-layer scanning, which can lay the foundation for afterward block body formation. Microstructure and properties of the block specimen prepared under the different SLM process parameter are studied by the density measurement and the scanning electronic microscope analysis. The forming parts with high density have been prepared under the optimal SLM process parameters.
Liu Bin, Bai Peikang, Li Yuxin North University of China, Taiyuan 030051, China