Analysis of fatigue failure and crack propagation of solid joints under vibration load

In this paper,the substructure technique is used to construct the finite element model of the printed circuit board(PCB) which EBGA package has been soldered onto and random vibration loading has been applied,then the influence of environment temperature and vibration frequency on the vibration fatigue life of solid joints is studied.Subsequently an advanced global/local finite element modeling tech-nique is employed to study the add-on effect of random vibration on the solid joint with pre-crack which is induced during thermal cycling test.The research result is helpful to prepare vibration test scheme and combine thermal cycling test with vibration test effectively.At last,the conclusion is validated by test.