1987 Volume 5 Issue 1 Pages 43-48
Dissimilar joint of nonferrous metals like as contact-bars of electromagnetic swtichgears are required both high quality at bonds and non-deformation of works.
For the purposes, vapor-shielded pressure bonding process and inprocess control system applicable to the process are developed.
From the view point of controlling work deformation, heating characteristics and temperature distribution while bonding is suggested to be controlled by computer simulation shown in the Report 1.
In this study, the actual proof for the computer simulation, clarification of heating mechanism at each material system and selection of electrode constitution to prevent the work deformation are experimentally examined for the joint couple of disk-shape Ag and Cu.
Results obtained are summarized as follows;
(1) Electrodes Mo-Mo give relatively flat temperature distribution all over the joint materials.
(2) Electrodes CuCr-CuCr can give the peak temperature at the bonding interface, so that the material (Ag) deformation is effectively controlled. But, twice current is necessary to bond in comparison with electrodes Mo-Mo.
(3) The computer simulation applied in the Report 1 is proved to be proper for estimating heating characteristics and temperature distribution in the bonding process, that is, both results of the experiments and the simulation agree with each other.
(4) Arrangement of electrodes such as CuCr to Ag side and Mo to Cu side can achieve a deformationfree bonding under relatively lower current condition and lower average temperature in Ag materials.
(5) In the above-mentioned constitution of electrodes, the optimum current range becomes to be enlarged. Since the allowable current limit against deformation extends to higher current condition.
