316L不锈钢增材成型件小孔钻削试验研究

Experimental research on small hole drilling of 316L stainless steel additive forming parts

为研究316L不锈钢增材成型件的制备并改善其小孔钻削工艺性,以316L不锈钢粉末为增材成型材料,采用激光熔覆技术在45钢表面制备得到了316L不锈钢增材成型件;利用光学显微镜观察分析了试件熔覆层截面显微组织,使用显微硬度计测试了熔覆层的显微硬度;搭建了钻削试验平台,采用单因素试验与正交试验相结合的试验方案,对传统工艺获得的316L不锈钢板材与316L不锈钢增材成型件进行了钻削对比试验;探究了钻削工艺参数对增材成型件钻削性能的影响规律以及最优的钻削工艺参数组合。结果发现,通过激光熔覆增材制造技术制备得到的316L增材成型件表面平整光滑,熔覆层与基体之间呈良好的冶金结合,熔覆层的硬度为570HV^610HV,是传统工艺获得的316L不锈钢板材硬度(约为200HV^300HV)的2倍左右;316L不锈钢增材成型件的钻削轴向力远小于传统工艺获得的316L不锈钢板材的钻削轴向力。激光熔覆增材制造技术能显著提高材料硬度并改善其切削加工性能。

In order to study the preparation of 316L stainless steel additive forming parts and improve its small hole drilling process,316L stainless steel powder was used as the additive forming material, and 316L stainless steel additive forming parts were prepared on the surface of 45 steel by laser cladding technology. The microstructure of the cladding layer of the test piece was observed by optical microscope. The microhardness of the cladding layer was tested by microhardness tester. A drilling test platform was built. The combination of single factor test and orthogonal test were used to compare the drilling test of 316L stainless steel additive forming specimens and 316L stainless steel additive formed by traditional process. The influence of drilling parameters on the drilling performance of additive forming specimens and the optimal combination of drilling process parameters were investigated. The results show that the surface of the 316L stainless steel forming parts formed by laser cladding additive manufacturing technology is smooth, and the metallurgical bond between the cladding additive layer and the substrate is good. The hardness of the cladding layer is 570 ~610HV,which is about twice the hardness of the 316L stainless steel sheet obtained by the traditional process( about 200 ~300HV);the axial force of the 316L stainless steel additive forming specimen is much smaller than the drilling axial force of the 316L stainless steel sheet obtained by the traditional process. Laser cladding additive manufacturing technology can significantly improve material hardness and improve its machinability.