温度对真空热压连接技术制备AZ31/Al/Ta复合材料界面组织和力学性能的影响

Effect of Temperature on Interface Microstructure and Mechanical Properties of AZ31/Al/Ta Composites Prepared by Vacuum Hot Compression Bonding

摘要:

采用真空热压连接方法制备了AZ31/Al/Ta复合材料。研究了热压温度对AZ31/Al/Ta复合材料界面组织演变、相组成及界面抗剪切强度的影响。探讨了AZ31/Al/Ta复合材料在真空热压连接工艺条件下的界面结合机理。结果表明，随着热压温度的升高，Mg-Al界面相组成由Mg-Al脆性金属间化合物（Al₁₂Mg₁₇和Al₃Mg₂）转变为Al-Mg固溶体。与400 ℃相比，450 ℃时Al/Ta界面扩散层宽度增大。在400和450 ℃时，AZ31/Al/Ta复合材料抗剪切强度分别为24和46 MPa。AZ31/Al/Ta复合材料界面结合机制为扩散与机械啮合共存。此外，避免界面脆性相的形成可以显著提高界面结合强度。

Abstract:

AZ31/Al/Ta composites were prepared using the vacuum hot compression bonding (VHCB) method. The effect of hot compressing temperature on the interface microstructure evolution, phase constitution, and shear strength at the interface was investigated. Moreover, the interface bonding mechanisms of the AZ31/Al/Ta composites during the VHCB process were explored. The results demonstrate that as the VHCB temperature increases, the phase composition of the interface between Mg and Al changes from the Mg-Al brittle intermetallic compounds (Al₁₂Mg₁₇ and Al₃Mg₂) to the Al-Mg solid solution. Meanwhile, the width of the Al/Ta interface diffusion layer at 450 °C increases compared to that at 400 °C. The shear strengths are 24 and 46 MPa at 400 and 450 °C, respectively. The interfacial bonding mechanism of AZ31/Al/Ta composites involves the coexistence of diffusion and mechanical meshing. Avoiding the formation of brittle phases at the interface can significantly improve interfacial bonding strength.