Contact Failure in Cyclically Thermally Stressed Connectors - Its Relationship between Micro Deformation Analysis by Means of Laser Holography

摘要

Contact resistance variations which some time may to reach failures were observed with respect to the contact mounted on the printed circuit board ( PCB ) and the PCB connector, which were thermally stressed. The Holographic Pattern Measuring System ( HPMS ) was applied to the thermal deformation analysis of the PCB surface and the PCB connector due to current flow, and it was shown that the HPMS was a very effective tool to measure the microscopic deformation pattern. From the experiments, the possibility was shown of quantitative investigation of contact phenomena which relates a small displacement of PCB mounted contact point by using the HPMS. For the connector contact, the thermal deformation of connector due to current and using a heating unit was observed, which may give us some suggestions on choosing contact pins for high current to supply a power to the PCB.