金属热处理 ›› 2020, Vol. 45 ›› Issue (8): 113-118.DOI: 10.13251/j.issn.0254-6051.2020.08.022

• 工艺研究 • 上一篇    下一篇

重熔及退火对316L不锈钢激光熔覆层残余应力的影响

邓德伟1,2, 马云波1, 马玉山3, 何涛3, 黄治冶2, 孙奇2   

  1. 1.大连理工大学 材料科学与工程学院, 辽宁 大连 116024;
    2.沈阳鼓风机集团股份有限公司 沈鼓-大工研究院, 辽宁 大连 116023;
    3.吴忠仪表有限责任公司, 宁夏 吴忠 751100
  • 收稿日期:2020-01-27 出版日期:2020-08-25 发布日期:2020-09-07
  • 作者简介:邓德伟(1974—),男,副教授,博士,主要研究方向为机械装备再制造、材料表面工程及金属3D打印等,E-mail: cailiaoqingqibing@163.com
  • 基金资助:
    辽宁重大装备制造协同创新中心基金(DUT2017031);沈鼓-大工重大科研发展基金;高端控制阀产业技术协同创新中心基金(2018WZ003);中央高校基本科研业务费专项资金

Influence of remelting and annealing on residual stress of 316L stainless steel laser clad layer

Deng Dewei1,2, Ma Yunbo1, Ma Yushan3, He Tao3, Huang Zhiye2, Sun Qi2   

  1. 1. School of Materials Science and Engineering, Dalian University of Technology, Dalian Liaoning 116024, China;
    2. SBW & DUT Research Institute, Shenyang Blower Works Group Corporation, Dalian Liaoning 116023, China;
    3. Wuzhong Instrument Co. , Ltd. , Wuzhong Ningxia 751100, China
  • Received:2020-01-27 Online:2020-08-25 Published:2020-09-07

摘要: 选用316L不锈钢粉末在Q235钢板上进行激光熔覆,并对熔覆试样进行了激光重熔和退火处理。利用盲孔法对熔覆层及基体的残余应力进行测试,采用光学显微镜、维氏硬度计对熔覆层进行微观组织观察和硬度测试。结果表明,激光重熔后熔覆层组织结构未发生显著改变;熔覆层经600 ℃退火2 h后晶粒有轻微长大,经800 ℃退火2 h后发生再结晶,枝状晶数量减少。经过激光重熔和退火工艺后,显微硬度仍维持较高值。激光重熔最多能使残余应力降低55.9%,而合理的退火处理工艺能使残余应力降低70%以上, 800 ℃退火2 h时残余应力的改善效果最显著,残余应力降低了83.8%。

关键词: 不锈钢, 激光熔覆, 残余应力, 激光重熔, 退火

Abstract: Laser cladding was carried out on Q235 steel substrate using 316L stainless steel powder, and then the clad specimens were treated by means of laser remelting and annealing. The residual stress of the clad layer and the substrate was measured through blind hole drilling. The microstructure observation and the hardness testing of the specimens were carried out respectively by optical microscope and Vickers hardness tester. The results show that the microstructure of the clad layer does not exhibit obvious changes after laser remelting. Annealed at temperature of 600 ℃ for 2 h, the grains of the clad layer grow slightly, while at 800 ℃ for 2 h recrystallization occurs and the number of dendrites decreases. The microhardness of the clad layer remains at a high level after the laser remelting and annealing. The laser remelting can reduce the clad layer residual stress by 55.9% at most, while the appropriate annealing process can reduce the residual stress by more than 70%. The annealing at 800 ℃ for 2 h can give the most significant improvement of residual stress reduction, by 83.8%.

Key words: stainless steel, laser cladding, residual stress, laser remelting, annealing

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