超声冲击细化22SiMn2TiB超高强钢焊接接头晶粒研究  

Investigation on Fining Grain of Ultrahigh Strength Steel Welding Joint by Ultrasonic Impact Treatment

作　　者：叶雄林[1] 朱有利[1] 

机构地区：[1]装甲兵工程学院装备再制造系,北京100072

出　　处：《热加工工艺》2006年第23期12-14,共3页Hot Working Technology

摘　　要：晶粒细化有助于提高焊接接头性能。应用超声冲击装置对母材为22SiMn2TiB、焊接材料为Cr20Ni10Mn6的异种钢焊接接头进行冲击强化试验,研究了冲击区域金属的塑性变形情况。用扫描电镜观测冲击层断面区,可看到冲击塑性变形层达到150μm,其中晶粒细化区超过50μm;用X-Ray衍射仪测试冲击层细晶衍射线宽化现象,并计算冲击层细化晶粒尺寸,计算结果表明母材冲击层平均晶粒尺寸为63nm,焊缝金属冲击层平均晶粒尺寸为82nm。研究表明,超声冲击时冲击针的高频大能量输入,引起冲击层金属晶格畸变,位错增殖、运动、重排,是晶粒细化的主要原因。Fining grain benefits to increase properties of weld joint. The peening-strengthening experiment of dissimilar steel welding joint specimens with base metal 22SiMn2TiB and welding rod Cr20Ni10Mn6 was carried out with ultrasonic impact tool.The metal plastic deformation of impacted area was investigated. The cross section of impacted area was observed by scan electron microscope. The result shows that plastic deformation layer is up to 150μm, in which the layer of fining grain is up to 50μm. The phenomenon of diffraction line widened that arose from grain fining of metal impacted layer was tested with XRD apparatus, and the grain size of impacted layer was computed. The results show that the average grain sizes of impacted layer are 63nm in base metal and 82nm in weld metal, respectively. The main reason of grain fining is crystal lattice deformation and dislocation reproduction,movement and rearrangement in impacted layer metal, which arises from induction of high frequency and large energy during ultrasonic impacting.

关 键 词：超声冲击处理 晶粒细化 焊接接头 塑性变形 

分 类 号：TG401[金属学及工艺—焊接] TG441.8