Abstract
Toward a sustainable society, there is a demand for multi-material structures that utilize aluminum, which has high electrical conductivity, is lightweight, and is easy to recycle. To realize the manufacturing of multi-material structures, the challenges are to develop a low-cost and versatile aluminum dissimilar material joining technology and a structure that facilitates a circular economy. With the aim of reducing costs and improving versatility, we have established a high-speed eutectic bonding method that generates and expels eutectic between aluminum and copper in a short time of less than one second by induced current flow in air, and are developing a joint bonding technology with the bonding strength to fracture the base material. In this study, in developing a joining judgment system for dissimilar metal bonding method using high-speed eutectic reaction, we developed a thermal analysis method that reduces the discrepancy between the temperature distribution obtained by energized experiment and that obtained by thermal analysis. This thermal analysis method consists of a process of deriving interface heat with pressure as a variable including energizing environmental factors, using energization heat balance experiment model, and a process of incorporating the obtained interface heat and uniform heating zone into general-purpose heat conduction analysis software to perform a thermal analysis of dissimilar metal bonding of any shape. The accuracy of thermal analysis was compared based on temperature distribution of experimental values and analyzed values, using bonding conditions of multi-material structure that obtains base metal fracture strength through high-speed eutectic reaction. Error rate was about 5% within 4 mm from the interface, which is a reasonable accuracy for determining conditions for bonding by eutectic reaction, and prospects for developing bonding judgment system were obtained.
