薄板TC4钛合金TIG电弧和激光焊接接头晶粒尺寸与微观组织

为探究焊接方法对316L不锈钢焊缝抗辐照损伤性能的影响，采用原子力显微镜(atomicforce microscopy, AFM )、扫描电子显微镜(scanning electron microscopy,SEM )、掠入射X射线衍射(grazing incidence X-ray diffraction,GIXRD )、拉伸和纳米压痕技术等方法，对不同焊接方法制备的经能量为70 keV、剂量为1 × 10¹⁷ ions/cm²的He ⁺ 辐照后的316L奥氏体不锈钢焊缝损伤情况及力学性能进行了研究. 结果表明，离子辐照后不同焊缝表面均产生了空洞等微观缺陷，力学性能呈现不同程度的降低. 辐照后TIG焊缝表现出更优异的抗辐照损伤性能. TIG焊缝中更多的缺陷阱有效阻碍了辐照点缺陷的相互聚集，使辐照后焊缝内形成的缺陷数量更少、尺寸更小. 表明改变焊接方法、细化焊缝晶粒来提高焊缝抗辐照损伤性能及抗辐照硬化性能，是一种可行的思路与方法.

Effect of Nb-free consumables on the microstructure and structural integrity of pressure vessel grades of dissimilar austenitic stainless steel welded joints

To explore the influence of welding methods on the irradiation damage resistance of 316L stainless steel welds, 316L austenitic stainless-steel welds prepared by different welding methods were exposed to He⁺ ions with 70 keV energy to a dose of 1 × 10¹⁷ ions/cm² at room temperature. The welds were analyzed using atomic force microscopy (AFM), scanning electron microscopy (SEM), grazing incident X-ray diffraction (GIXRD), tensile testing, and nanoindentation techniques. The results showed that microdefects such as voids appeared on the surfaces of different weld joints after ion irradiation, and the mechanical properties decreased to varying degrees. TIG welds exhibited better irradiation damage resistance after irradiation. This is because more defect traps in TIG welds effectively prevent the mutual aggregation of irradiation point defects, resulting in fewer and smaller defects formed in the weld after irradiation. This indicates that refining the weld grain and improving weld resistance to irradiation damage and irradiation hardening by changing the welding method is a feasible idea and method.