选区激光熔化钴铬合金的性能研究

发布时间：2019-06-25 13:37

【摘要】：利用自主开发的选区激光熔化设备以钴铬合金为成型材料,在进行了系统的工艺优化研究的基础上,对选区激光熔化(SLM)制件成型过程中表面粗糙度演化、微观形貌、致密度以及硬度之间的内在联系进行了研究。研究发现:成型过程中粉层的熔化收缩以及厚度的累积是造成成型质量变差的重要原因;较小的表面粗糙度累积效应,可大大减少成型件内部的孔隙数量从而提高致密度,粉层厚度的降低是减小表面粗糙度累积效应和提高致密度的关键;制件的宏观硬度比显微硬度对制件致密度存在更显著的依赖关系:致密度越大,宏观硬度越大。通过优化工艺制得的工件致密度达到98.04%,宏观硬度为40HRC,符合美国材料实验协会(ASTM)标准。
[Abstract]:Using selective laser melting equipment developed by ourselves, cobalt-chromium alloy was used as molding material. On the basis of systematic process optimization research, the internal relationship among surface roughness evolution, micromorphology, density and hardness in the process of selective laser melting (SLM) parts was studied. It is found that the melting shrinkage and thickness accumulation of powder layer are the important reasons for the deterioration of molding quality, and the small cumulative effect of surface roughness can greatly reduce the number of pores in the molding parts and increase the density, and the decrease of powder layer thickness is the key to reduce the cumulative effect of surface roughness and increase the density. The macro hardness of the parts depends more significantly on the density of the parts than the microhardness: the higher the density is, the greater the macro hardness is. The density of the workpiece prepared by the optimized process is 98.04%, and the macro hardness is 40HRC, which accords with the (ASTM) standard of the American Materials experiment Association.
【作者单位】：北京工业大学激光工程研究院;
【基金】：北京市科委重大课题(Z141100002814011)
【分类号】：TG665

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