激光喷丸与机械喷丸对304不锈钢应力腐蚀性能的影响

Effect of laser peening and shot peening on stress corrosion sensitivity of 304 stainless steel

对304不锈钢板试样分别进行了激光喷丸与机械喷丸处理,采用X射线衍射仪分析了表层显微组织和晶粒尺寸的变化,通过慢应变速率拉伸腐蚀试验检测了应力腐蚀敏感性。结果表明,通过激光喷丸处理,表层晶粒得到了细化,但没有产生明显的马氏体相变,随着喷丸能量密度增大,应力腐蚀敏感性减小;而通过机械喷丸处理的试样,晶粒细化的同时诱发了明显的马氏体相变,随着喷丸压力升高,应力腐蚀敏感性呈现先减小后增大的变化趋势。

The 304 stainless steel specimens were treated by shot-peening( SP) and laser-peening( LP) respectively. The grain size and metallographic organization of the specimen surface layer was tested with the X-ray diffraction method,and the stress corrosion sensitivity was analyzed use the slow strain rate tests( SSRT). The results show that surface layer grains of the specimen are obviously refined after being treated by LP,but no significant martensitic transformation is found,with the increase of LP energy density,the stress corrosion sensitivity decreases gradully; While both the grain refinement and significant martensitic transformation are found at the surface of the specimen treated by SP,with the increase of SP pressures,the stress corrosion sensitivity decreases at first,and then increases.