镍基合金激光直接制造的显微组织与缺陷分析

采用FGH95镍基高温合金粉末进行激光直接制造工艺实验,研究了不同工艺参数对表面形貌、显微组织和显微硬度的影响。结果表明,成形件表面平整无变形,显微组织为细小而致密的柱状晶,有层内生长和外延式生长两种生长方式。同时对其中出现的缺陷也作了研究分析,得到了优化的工艺参数。

Investigation on Microstructure and Defect of Ni-based Alloys Fabricated by Laser Direct Manufacturing (LDM)

The cubic metal blocks of Ni-based powders of FGH95 were fabricated by LDM. Surface appearance, microstructure and microhardness of the samples manufactured by different parameters were studied. The results show that the surface of the as-manufactured blocks is smooth and no apparent distortion ,the microstructure is made up of fine and dense columnar dendritic,which have two growth modes inner-layer and epitaxial growth. The defects in the samples were also analyzed and the optimal processing parameters were acquired.