Ti/Nb作中间层脉冲加压扩散连接TiC金属陶瓷与不锈钢

用Ti/Nb作中间层,在温度890℃、时间4~12min、脉冲压力2~10MPa、频率f=0.5Hz、恒压10MPa下,对TiC金属陶瓷和304不锈钢(304SS)进行脉冲加压与恒压扩散焊,获得了牢固的固相扩散焊接头。通过扫描电镜SEM、能谱EDS、X射线衍射XRD与剪切性能测试,对接头的显微组织、界面产物与强度进行分析。结果显示:两种接头的界面物相相似,主要有σ相,(β-Ti,Nb)与α+β-Ti固溶体。连接时间10min时,恒压下的TiC/304SS接头抗剪强度为55.6MPa,而脉冲加压下的接头抗剪强度达110MPa。恒压下接头断裂方式为TiC陶瓷断裂,而脉冲压力下接头断裂方式为TiC陶瓷与界面产物间交替进行的混合断裂。

Impulse Pressuring Diffusion Bonding of TiC Cermet to Stainless Steel Using Ti/Nb Interlayer

Impulse pressuring diffusion bonding(IPDB) and constant pressuring diffusion bonding (CPDB) of TiC cermet to 304 stainless steel(304SS) using Ti/Nb interlayer was carried out at 890℃ under a impulse pressuring of 2-10MPa and a constant pressuring of 10MPa within a duration of only 4-12min,and a robust metallurgical bonding was achieved.Microstructure characterization and shear performance of the IPDB and CPDB joints were analyzed by SEM,EDS,XRD and shearing test.The results show that the interface phases in those two kinds of joints are similar,which are mainly σ phase,(β-Ti,Nb) and α+β-Ti solid solution.When the joint is bonded for 10min,shear strength of TiC/304SS CPDB joints is 55.6MPa,while the shear strength of IPDB joints reaches 110MPa.The fracture of CPDB joints is TiC cermet fracture,while that of IPDB joints is mixed fracture by alternated between TiC cermet and reaction layer.