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Selective laser melting (SelectiveLaserMelting, SLM) is the mid-nineties proposed a new type of rapid prototyping technology, which is manufactured using laser, the purpose is to create a high density, good mechanical properties of complex metal parts, in order to fill the existing lack of rapid prototyping technology. At present, the rapid prototyping technology has become an overseas research priorities, while China is still in the exploratory stage tracking. Key technologies of SLM includes three aspects, namely SLM forming apparatus, the use of a metal powder material and a set of process parameters; its main technical difficulties during the forming process prone ball phenomenon, thus affecting the densification SLM and forming parts internal structure. In this paper, the current research status, the choice of stainless steel powder as the experimental materials, mainly from two aspects discussed SLM forming quality factors. One is formed from the SLM to study the properties of the metal powder material, by selecting appropriate process parameters, the same process conditions, respectively, the three material 316L stainless steel powder molding experiments, the forming parts of the strength test and observe its microscopic morphology, particle size distribution analysis, the powder particle shape and powder ingredients especially oxygen for forming parts quality. Forming the other process parameters from the SLM settings up study to consider parameters including laser power, scanning speed, scan mode, scan spacing, powder layer thickness. The main verification experiment forming a single channel scanning, single-scan shape, forming three kinds of scanning the block, is fixed under other process conditions, a single change in one of the process parameters, the results summarized on the forming quality of the parameters were investigated. After getting the powder characteristics and process parameters on the quality of SLM law, the paper forming process from the SLM pool formation, shape, mutual superposition of the angle of the laws of the formation mechanism of these effects. Another article also SLM and hot isostatic pressing of composite forming technology for the exploratory research, analysis of this complex variety of process routes forming technology feasibility and design through SLM built bulk metal powder forming a metal sheath , and then by hot isostatic pressing process the last generation dense parts. Through experimental demonstration, preliminary findings after hot isostatic pressing process can improve the density of SLM forming parts.
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