Interface cracking of plastic electronic package under temperature and humidity environment

Structural model of plastic electronic package under temperature and humidity is constructed, and the coupling of the thermal and moisture impact on structure field is implemented. The impact of thermal expansion, hygro-swelling and vapor pressure increases with increasing initial defect, especially the impact of vapor pressure. At certain crack length, K-I and K-II induced by thermal expansion is proportional to temperature difference, and K-I and K-II induced by vapor is proportional to vapor pressure. The impacts of thermal expansion and hygro-swelling on ERR decrease during crack propagation, but the impact of vapor pressure increases significantly.