电场激活辅助AlMgB14-TiB2与金属的反应扩散连接及界面结构分析

Reactive Diffusion Bonding of AlMgB14-TiB2 to Metal by FAPAS and Interfacial Structure Analysis

摘要:

采用FAPAS烧结工艺原位合成了AlMgB14-TiB2复合材料，并分别同步实现了与金属Nb和 Mo的扩散连接。利用XRD、SEM和 EDS等手段对连接界面扩散层的相组成、微观形貌和元素分布特征进行了分析；探讨了在电场、温度场、压力场多物理场耦合条件下的扩散层形成机制及扩散连接过程。结果表明，AlMgB14-30%(质量分数)TiB2复合材料与金属Nb和 Mo可以实现同步合成和扩散连接，形成宽170~180 μm的均匀致密的扩散连接层；TiB2在烧结过程中富集于连接界面，并与金属反应生成金属间化合物；硼元素在浓度梯度作用下的连续扩散和金属间化合物的形成是扩散连接的主要机制。

Abstract:

The in-situ synthesis of AlMgB14-TiB2 composite and its simultaneous diffusion bonding to Nb and Mo were achieved by FAPAS sintering process. XRD, SEM and EDS were used to analyze the phase composition, microstructure and elements distribution characteristics in the joint interface; the formation mechanism of diffusion layer and the process of diffusion bonding under multi-physics coupling condition (electric field, temperature field and pressure field) were discussed. Results indicate that the simultaneous synthesis and diffusion bonding of AlMgB14-30 wt%TiB2 composites to Nb and Mo could be realized, forming uniform and dense diffusion layers with an average width of about 170~180 μm; TiB2 particles gather in the joint interface during the sintering process and react with the metal to form intermetallic compounds; the continuous diffusion of boron element driven by concentration gradient and the formation of intermetallic compounds are the main mechanisms in diffusion bonding.