金属热处理 ›› 2023, Vol. 48 ›› Issue (5): 174-183.DOI: 10.13251/j.issn.0254-6051.2023.05.027

• 工艺研究 • 上一篇    下一篇

固溶处理对选区激光熔化双相不锈钢组织及性能的影响

杨智凯1, 张欣悦2, 易林3, 闫星辰2, 王志1   

  1. 1.石家庄铁道大学 材料科学与工程学院, 河北 石家庄 050043;
    2.广东省科学院新材料研究所现代材料表面工程技术国家工程实验室, 广东省现代表面工程技术重点实验室, 广东 广州 510650;
    3.湘潭大学 材料科学与工程学院, 湖南 湘潭 411105
  • 收稿日期:2022-10-24 修回日期:2023-03-17 出版日期:2023-05-25 发布日期:2023-06-21
  • 通讯作者: 王 志,讲师,博士,E-mail: zhiwang_stdu@126.com
  • 作者简介:杨智凯(1996—),男,硕士,主要研究方向为金属增材制造,E-mail: 381243699@qq.com。
  • 基金资助:
    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)

Effect of solution treatment on microstructure and properties of selective laser melted duplex stainless steel

Yang Zhikai1, Zhang Xinyue2, Yi Lin3, Yan Xingchen2, Wang Zhi1   

  1. 1. School of Materials Science and Engineering, Shijiazhuang Tiedao University, Shijiazhuang Hebei 050043, China;
    2. 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;
    3. School of Materials Science and Engineering, Xiangtan University, Xiangtan Hunan 411105, China
  • Received:2022-10-24 Revised:2023-03-17 Online:2023-05-25 Published:2023-06-21

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80 μm,铺粉层厚50 μm。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%。

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

Abstract: 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 80 μm and thick of powder layer of 50 μm. 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 brittle σ phases on the grain boundary, greatly weakening the plasticity of the specimen. When the solution temperature rises to 1020 ℃ or above, σ phase 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%.

Key words: selective laser melting, duplex stainless steel, solution treatment, microstructure, mechanical properties

中图分类号: