(大连理工大学 精密与特种加工教育部重点实验室，大连 116024)
摘 要: 采用脉冲激光实现304不锈钢与C-276合金异种材料的焊接成形，利用几何方法计算不同激光能量偏移量条件下C-276在焊缝中的熔化比例，借助电子探针对焊缝主要元素进行宏观分析，获得C-276熔化比例与焊缝Fe、Ni两大元素在焊缝处的分布关系，并检测不同激光能量偏移条件下焊缝的力学性能。结果表明：304/C-276各异质焊缝化学元素分布均匀，且过渡区较窄，激光能量偏移量对异质焊缝元素含量影响较为显著，随着激光能量偏移量的增加，焊缝中Ni、Mo和W元素逐渐增多，Fe元素逐渐减少，Cr元素变化不大；C-276熔化比例与焊缝中Fe和Ni元素分布满足杠杆原理；304/C-276各异质焊缝的抗拉极限强度均低于304和C-276母材的，当激光能量偏向C-276母材+0.2~ +0.3 mm时，焊缝抗拉极限强度达到最佳状态。
关键字: 激光异质焊接；能量偏移；元素分布；抗拉强度
（Key Laboratory for Precision and Non-traditional Machining Technology, Ministry of Education,
Dalian University of Technology, Dalian 116024, China）
Abstract:The technology of welding 304 stainless steel to C-276 alloy with Nd:YAG pulsed laser was carried out. The fusion ratio of C-276 in the weld joint was achieved with geometric method under the condition of different laser energy offsets. Macroscopic analysis of the main elements distribution in the weld joint was deeply studied by electron probe. The relationship between C-276 confuse ratio and compositions of Fe and Ni in the weld joint was achieved. Then, tensile test was carried out to detect the mechanical properties of the weld joint. The results indicate that, under the condition of different laser energy offsets, the main elements in dissimilar weld joint distribute uniformly. Laser energy offsets affect the elements composition significantly. With the increase of the laser energy offsets, Ni, Mo and W elements increase gradually, Fe element gradually reduces and Cr element changes little. The relationship between C-276 confuse ratio and compositions of Fe and Ni meets the leverage principle. Under the condition of different laser energy offsets, the ultimate tensile strength of weld joint is lower than those of 304 and C-276 base metal. As the laser energy moves to C-276 for about +0.2-+0.30 mm, the ultimate tensile strength of weld joint reaches the best.
Key words: laser dissimilar welding; energy offset; element distribution; tensile strength
