This research work was mainly concerned to investigate the effect of bonding temperature on the weldability of CoCrNi MEA with SUS 304 stainless steel. Shear test and nano hardness measurements were used to evaluate the mechanical performance of the welded joints. The formation of IMCs intensified along with the bond interface when samples were treated at low bonding temperature (i.e., 925 °C) which badly affected the joint’s shear strength. Reduction in IMCs formation transpired as the bonding temperature increase, and eventually, the formation of the solid solution was instigated at the bond interface. Furthermore, at 1075 °C bonding temperature, the bond interface was almost free from IMCs and transformed to a solid solution, triggering the enhancement of the joint’s shear strength. SEM with EDX, XRD, and thermal analysis was used for microstructural examination to comprehend the interface reaction/bond formation mechanism during the welding process. Moreover, a thermodynamic description is also provided to predict the phase formation at the bond interface. In this regard, established rules (i.e., ΔH_mix, ΔS_mix, Ω, and δ) to determine the phase stability of HEAs were implemented which found valid in predicting the phase formation at the bond interface.

本研究工作主要是研究结合温度对 CoCrNi MEA 与 SUS 304 不锈钢焊接性能的影响。剪切试验和纳米硬度测量用于评估焊接接头的机械性能。当样品在低粘合温度（即 925°C）下处理时，IMC 的形成与粘合界面一起加剧，这严重影响了接头的剪切强度。随着键合温度的升高，IMCs 的形成会减少，最终，在键合界面处引发了固溶体的形成。此外，在 1075 °C 的键合温度下，键合界面几乎没有 IMCs 并转化为固溶体，触发接头剪切强度的增强。SEM 与 EDX、XRD、并使用热分析进行显微组织检查，以了解焊接过程中的界面反应/键形成机制。此外，还提供了热力学描述以预测键界面处的相形成。在这方面，既定规则（即 ΔH _mix、Δ S _mix、Ω和δ ) 来确定 HEA 的相稳定性，这在预测键界面处的相形成方面是有效的。