摘要
通过设计和优化双相不锈钢激光选区熔化(SLM)成形工艺,制得了高精度、低缺陷密度的(21.98wt%Cr-5.37wt%Ni-3.13wt%Mo-1.95wt%Mn)双相不锈钢,进一步研究了不同固溶处理温度对其显微组织和性能的影响。结果表明,通过对不同工艺参数SLM成形试样的研究,得到最佳SLM工艺参数:激光功率275 W,激光扫描速度700 mm/s,扫描间距80μm,铺粉层厚50μm。固溶处理能有效地调控SLM成形双相不锈钢的相组成及比例,试样中奥氏体含量均较打印态试样大幅提高。较低温度固溶处理会导致脆性σ相在晶界处析出,大幅削弱试样的塑性。当固溶温度升高到1020℃及以上时,σ相消失。更高的固溶处理温度又会使晶粒粗化,既降低试样的强度又损害塑性。1020℃固溶处理试样中可获得接近平衡的双相组织,此时抗拉强度为868 MPa,伸长率达到35.0%。
By designing and optimizing the selective laser melting(SLM)forming process for duplex stainless steel,a duplex stainless steel(21.98wt%Cr-5.37wt%Ni-3.13wt%Mo-1.95wt%Mn)with high accuracy and low defect density was produced.The effect of different solution treatment temperatures on its microstructure and properties was further studied.The results show that the optimal SLM processing parameters obtained through the study of the SLMed specimens under different processing parameters are laser power of 275 W,scanning speed of 700 mm/s,scanning space of 80μm and thick of powder layer of 50μm.Solution treatment can effectively regulate the phase composition and proportion of the SLMed duplex stainless steel,and the austenite content of the specimen is significantly higher than that of the as-printed specimen.Solution treatment at lower temperatures can lead to the precipitation of brittleσphases on the grain boundary,greatly weakening the plasticity of the specimen.When the solution temperature rises to 1020℃or above,σphase disappears.Higher solution treatment temperatures can also coarsen the grains,not only reducing the strength of the specimen,but also decreasing the plasticity.When solution treated at 1020℃,a nearly equilibrium dual-phase structure is obtained in the specimen,of which the tensile strength is 868 MPa and the elongation reaches 35.0%.
作者
杨智凯
张欣悦
易林
闫星辰
王志
Yang Zhikai;Zhang Xinyue;Yi Lin;Yan Xingchen;Wang Zhi(School of Materials Science and Engineering,Shijiazhuang Tiedao University,Shijiazhuang Hebei 050043,China;Institute of New Materials,Guangdong Academy of Sciences,National Engineering Laboratory for Modern Materials Surface Engineering Technology,Guangdong Provincial Key Laboratory of Modern Surface Engineering Technology,Guangzhou Guangdong 510650,China;School of Materials Science and Engineering,Xiangtan University,Xiangtan Hunan 411105,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2023年第5期174-183,共10页
Heat Treatment of Metals
基金
广东省重点领域研发计划(2020B090923002)
河北省青年科学基金(E2021210094)
广东省科学院发展专项资金(2020GDASYL-20200103108,2022GDASZH-2022010107)
广东省基础与应用基础研究基金(2019A1515011841)
广州市科技计划(202102020327)。
关键词
选区激光熔化
双相不锈钢
固溶处理
显微组织
力学性能
selective laser melting
duplex stainless steel
solution treatment
microstructure
mechanical properties
