To improve the quality of welded joints between copper and 316L stainless steel, laser welding with Ni interlayer was carried out. A sound welded joint was obtained and the microstructures as well as mechanical properties were investigated. Results indicate that no welding defects or spherical particles were formed in the fusion zone. The microstructures in the fusion zone were characterized as dendritic grains, and no macroscopic segregation was observed. The welded joint failed at copper base material with an average tensile strength of 408 MPa at 77 K, and ductile fracture mode with dimples on the fracture surface were presented. Moreover, the addition of Ni interlayer prevents formation of welding defects and spherical particles and improves mechanical properties of the joint.

为提高铜与316L不锈钢焊接接头质量，开展了带Ni夹层的激光焊接。获得了良好的焊接接头，并研究了显微组织和机械性能。结果表明在熔合区没有形成焊接缺陷或球形颗粒。熔合区的显微组织为树枝状晶粒，未观察到宏观偏析。焊接接头在铜基材料处失效，在 77 K 时的平均抗拉强度为 408 MPa，并呈现出断裂表面有凹坑的韧性断裂模式。此外，Ni夹层的加入防止了焊接缺陷和球形颗粒的形成，提高了接头的机械性能。