镍基钎料真空钎焊316L不锈钢钎焊接头组织转变的研究(英文)  

Microstructural Evolution during Vacuum Brazing of 316L Stainless Steel Using Nickel-Based Filler Metal

作　　者：于治水[1] 石昆[1] 言智[1] 李军[1] 李瑞峰[2] 

机构地区：[1]上海工程技术大学,上海201620 [2]江苏科技大学,江苏镇江212003

出　　处：《稀有金属材料与工程》2011年第S2期342-346,共5页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China (50875160)

摘　　要：使用质量比为 6:4 的混合镍基钎料 BNi-2 与 BNi-5 对 316L 不锈钢进行真空钎焊。由于钎缝间隙对钎焊接头组织性能有重要影响,所以在钎焊温度 1140 ℃,保温时间 10 min 的钎焊参数下,分别对钎缝间隙为 30,60 和 100 μm进行了钎焊实验。主要通过光学显微镜、扫描电子显微镜、能谱分析仪、电子探针显微分析仪以及显微硬度计等对钎焊接头界面组织特征进行分析。结果表明,分布于钎焊接头中心连续共晶组织是导致裂纹扩展的主要通道。另外,研究发现当进行完整的等温凝固过程时,只有γ-Ni 固溶体相存在于钎焊接头中,但在钎缝与母材边界的沿晶界区域仍存在第二相的金属间化合物。316L stainless steel was vacuum brazed using a composite nickel based brazing filler of BNi-2(60wt%) + BNi-5(40 wt%). Brazing experiment was conducted at 1140 ℃ for 10 min with different joint gap size of 30, 60 and 100 μm, respectively for the brazing clearance is crucial to the property of brazed joints. The interfacial microstructural characterization of the brazed joints were studied by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry(EDS), electron probe microanalyzer(EPMA) and microindentation hardness meter. The results show that the presence of continuously distributed centerline eutectic constituents can result in a preferred low resistance path for crack propagation. Additionally, it is found that when isothermal solidification is completed, only γ-Ni phase appeared in the brazed interlayer; however, second phase of intermetallic particles along the grain boundary is still observed.

关 键 词：真空钎焊 不锈钢 镍基钎料 

分 类 号：TG454[金属学及工艺—焊接]