1988 Volume 6 Issue 1 Pages 116-123
The bonds in various electric devices are recently required high precision and high quality at bonds.
To control the material deformation, thermo-characteristics by resistance heating while bonding are examined, and the optimum electrode materials and their constitution are selected as described in the report-1 and the report-2.
To get high quality for bonds, examinations about defects at the interface are done, and then the vapor shield process for cleaning interface is newly developed. Moreover, the effects of the vapor shield process on preventing defect formation is successfully proved as described in the report-3 and in the report-4.
In this study, to apply the above process named Vapor Shielded Pressure Bonding on mass-production line of contact-bars of electromagnetic switchgears, the monitoring process of metal expulsion which is conclusive fatter of bonding quality and inprocess quality control system are examined.
The main results obtained are as follows;
1) Metal expulsion volumes fluctuate in continuous bonding of a number of contact-bars, because both the alterations of material properties and supplied power bring fluctuation of heat inputs.
2) In finding metal expulsion volume of each bonding by electrode displacement, the correct volume can be detected by employing forging stage before bonding. For, alteration of surface confiugration of contact materials which obstruct the correct detecting of expulsion can be effectively neglected by forging.
3) The beginning point of expulsion while bonding can be found accurately in real time by monitoring electrode displacement.
4) The inprocess control system by monitoring electrode displacement is successfully developed. The system can continuously produce the sound bonds of contactbars without any bad one.