喷丸压力和时间对304不锈钢焊接接头组织性能的影响

Effects of shot peening pressure and time on structure and properties of welded joint of 304 stainless steel

采用不同的喷丸压力和喷丸时间参数,对304不锈钢焊接接头进行高能喷丸处理。通过X射线衍射方法(XRD)检测了试样表层的晶粒尺寸和组织,并用显微硬度计测量了试样表层的显微硬度。结果表明,经高能喷丸处理后,304不锈钢焊接接头表层晶粒明显细化,达到纳米级,随着喷丸压力或喷丸时间的增加,晶粒尺寸逐渐变小,表层硬度随之增加;高能弹丸强烈冲击,使焊接接头表层产生塑性变形,并诱发马氏体相变,随着喷丸压力增大或喷丸时间增加,马氏体相比例逐渐增大。

304 stainless steel welded joint was treated by high-energy shot peening with different shot peening pressure and shot peening time. The grain size and structure of the specimen surface layer were tested with X-ray diffraction method（XRD） and the surface hardness was measured by microhardness tester. The results show that the surface layer gins of the specimens is obviously refined after high-energy shot peening, the grain size reaches nanometer level; as the shot peening pressure or the shot peening time increases, grain size becomes smaller and surface hardness increases, The welded joint surface layer produces plastic deformation under the strong impact of high energy projectiles, and the strain-induced martensitic transformation occures and it is found that the martensite phase ratio increases gradually with the increasing of shot peening pressure and shot peening time.