Evaluation of Potting Compounds by Electrical Resistivity Techniques Using the Continuous Current Monitoring Device (CCMD)

摘要

The Continuous Current Monitoring Device (CCMD) for evaluating potting compounds was first reported in 1956. It is based upon electrical resistivity measurement techniques. As the use of epoxy resin systems for potting electronics increased, a need was felt to know more about the polymerization process in relationship to the storage life of the potted units. CCMD was found eminently suitable for evaluating the long-term stability of such epoxy resins. The normal calculation and plotting of the test data is time consuming, so this part of the data analysis was computerized. All the computer programs are included in the appendices. The purpose of the report is to review the subject of CCMD evaluation of potting compounds and to discuss the latest methods for calculating and presenting the results. A typical analysis for one epoxy resin system, formulated into cured compounds ranging from very rigid to very flexible, is used to illustrate the use and interpretation of the CCMD data. Previously reported data are also given to further illustrate data analysis techniques. (Author Modified Abstract)