学术论文

      激光冲击处理不锈钢慢应变速率拉伸应力腐蚀性能

      Stress corrosion cracking of laser shock processed stainless steel by slow strain rate test

      摘要:
      利用激光冲击处理技术对304不锈钢片试样进行激光冲击处理.采用慢应变速率拉伸实验方法评价304不锈钢激光冲击处理前后在80 ℃时、质量分数为3.5%NaCl溶液中的应力腐蚀开裂敏感性.通过金相显微镜(OM)和扫描电子显微镜(SEM)分析激光冲击处理后表面强化层的晶粒细化程度.采用显微硬度计测定了表面显微硬度分布及影响层深度.实验结果表明,激光冲击处理未能显著细化试样表层晶粒,但可以提高显微硬度.随着冲击次数增加,表面显微硬度值也增加,影响层厚度提高.慢应变速率拉伸应力腐蚀试验结果表明激光冲击处理可以降低不锈钢应力腐蚀开裂敏感性,且双面冲击处理比单面冲击处理效果更好.
      Abstract:
      The 304 stainless steel was processed by laser shock processing (LSP).The stress corrosion cracking (SCC) behavior of 304 stainless steel specimen before and after LSP was evaluated using slow strain rate test (SSRT)in 3.5% NaCl solution at 80 ℃.Surface microstructure modification was evaluated by optical microscopy (OM) and scanning electron microscopy (SEM).Micro-hardness distribution in depth and affected depth were investigated by the micro-hardness tester.Results showed that surface refined grains were not found after LSP.However, micro-hardness was increased by LSP.With the increase of shot number, micro-hardness and thickness of affected layer were increased.SSRT results showed that SCC sensitivities of 304 stainless steel were decreased by LSP.SCC sensitivities of two-side LSP with higher resistance were lower than those of one-side one.
      作者: 魏新龙 凌祥 张萌
      Author: WEI Xinlong LING Xiang ZHANG Meng
      作者单位: 南京工业大学 机械与动力工程学院,江苏南京,211800
      年,卷(期): 2017, 39(3)
      分类号: TG172.5
      在线出版日期: 2017年7月3日
      基金项目: 国家自然科学基金,江苏省普通高校研究生科研创新计划