16MnR钢激光冲击工艺及对焊接结构应力腐蚀性能的影响EI北大核心CSCD

对16MnR母材进行激光冲击工艺实验,获得优化的激光冲击工艺参数。对激光-MAG复合焊焊接接头进行表面处理,分析接头激光冲击前后状态的残余应力分布及抗应力腐蚀性能变化。结果表明:对16MnR钢平板经激光冲击处理后,在材料表面最大可引入475μm厚度的塑性变形层,并同时引入-593 MPa的压应力分布。采用优化激光冲击工艺对16MnR钢焊接接头进行表面处理后,可有效减小焊接接头表面的残余拉应力分布。在3.5%NaCl(质量分数)条件下对激光冲击处理前后的接头试样进行慢应变速率应力腐蚀实验,发现激光冲击处理前后16MnR钢焊接接头的应力腐蚀敏感指数I_(SSRT)分别为0.106和0.104,表明激光冲击可以提高接头的抗应力腐蚀能力。

Laser peening process of 16MnR steel and effect on stress corrosion property of welded structure

The laser peening test carried out on the base material 16MnR steel to obtain the optimized process parameters. The residual stress distribution and stress corrosion resistance of the joint before and after laser-MAG hybrid welding were analyzed.The results show that the maximum plastic deformation layer of 475 μm thick and compressive stress distribution of -593 MPa can be introduced on the surface of 16MnR steel plate after laser peening treatment. By performing the optimized laser shock process, the residual tensile stress distribution on the welded joint surface can be effectively reduced.The slow strain rate stress corrosion tests were carried out on the joint samples before and after laser peening treatment under the condition of 3.5%NaCl(mass fraction). The results show that the stress corrosion sensitivity index I_SSRT of the 16MnR steel welded joints before and after laser peening are 0.106 and 0.104, respectively. The I_SSRT index of the welded joint samples decreases after the impact treatment, which indicates that the stress corrosion resistance of the welded joints increases.