激光直接烧结成形金属零件的实验研究

分析了激光熔池的动态快速冷凝及“球化”效应机理，基于此采用激光烧结直接成形工艺对铁粉和Ni45合金粉末进行了一系列的激光烧结实验。结果表明,直接烧结单组元铁粉易出现翘曲变形和“球化效应”，成形质量不高，即使调整工艺参数获得多层烧结件，但致密度较低;而在基体上烧结Ni45合金粉末,在合适的工艺参数下获得了致密组织较好的多层烧结件，内部组织细密均匀，表面光滑平整，且与基体结合牢固。

Experimental Research on Laser Direct Sintering of Metal Parts

This paper analyses the mechanism of dynamical condensation of the laser molten pool and balling effect. Direct metal laser sintering process was used to carry out series of sintering experiments of Fe powder and Ni45 alloy powder. The result indicated that it was easy to appear warpage deformation and balling effect during direct sintering metal powder, and the formation quality of the parts was bad, though getting multi-layers sintered part by adjust process parameters, the density was low. But by using appropriate process parameters, much densification sintered parts by sintering small grain size Ni45 alloy powder can be obtained, its microstructure was fine and uniform, surface smooth and bonding firmly with substrate.