Recent reports on sintering and bonding using the pulsed electric current bonding process indicate that the metals are subjected to Joule heating due to the electrical resistance at points of contact. However, the influence of bonding conditions on local heating phenomena remains unclear. In this study, to produce clear guidelines on the selection of parameters (bonding pressure, bonding surface roughness, initial current) for pulsed current bonding, joints of SUS304 stainless steel were formed under a variety of conditions.
It was found that the local heating efficiency at the bonded interface becomes larger with high resistance at the contact area when bonding pressure is lower and the bonding surface is smooth. When the initial current is high, local heating at the contact area is accelerated and joint quality is better. However, the initial current has an optimum value. Above this value the current tends to flow at the center of the bonding area, making it difficult to heat the bonding area uniformly.