摘要
对选区激光熔化(selective laser melting,SLM)316L不锈钢的拉伸性能及断裂机制进行了研究,并对拉伸断裂后的试样进行显微组织表征与分析,探究了拉伸变形过程中微观组织的演化规律。结果表明:采用选区激光熔化技术制备的316L不锈钢具有较好的强塑性匹配,其中晶粒内部纳米尺度胞状结构有助于强度的提升;其拉伸性能明显优于传统手段制备的316L不锈钢。选区激光熔化316L不锈钢在拉伸过程中奥氏体晶粒内部产生形变孪晶,并且形变孪晶的出现存在取向相关,在取向接近<001>的晶粒中不易出现,而在取向接近<110>-<111>的晶粒中较易出现。
Selective laser melting(SLM),as the most common additive manufacturing(AM)method,is capable of manufacturing metallic components with complex shape layer by layer.Compared with conventional manufacturing technologies such as casting or forging,the SLM technology has the advantages of high degree accuracy,high material utilization rate and environmentally friendly,and has attracted great attention in the fields of aerospace,nuclear power and medicine.The 316L austenitic stainless steel is widely used in the industrial field because of the excellent corrosion resistance and plasticity.It is also one of the commonly used material systems for SLM.In this work,the tensile properties and fracture mechanism of 316L stainless steel fabricated via SLM technology were investigated.The microstructure of the SLMed 316L specimens after tensile fracture was characterized and analyzed.The results show that the SLMed 316L stainless steel has a relatively desirable combination of strength and ductility,and its tensile performance is obviously better than that of 316L stainless steel prepared by traditional methods.The nanometer-scale cell structure inside the grain contributes to the improvement of strength.Deformation twins were observed in the SLMed 316L stainless steel after tensile test.The appearance of twins is oriented-dependent,and it is easy to occur in the grain with the direction near<110>-<111>.
作者
余晨帆
赵聪聪
张哲峰
刘伟
YU Chenfan;ZHAO Congcong;ZHANG Zhefeng;LIU Wei(School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China;Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China)
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第5期683-692,共10页
Acta Metallurgica Sinica
基金
国家磁约束核聚变能发展研究专项项目No.2014GB117000。
关键词
选区激光熔化
316L不锈钢
拉伸性能
形变孪晶
selective laser melting
316L stainless steel
tensile property
deformation twinning
