Fracture failure analysis of 50CrVA steel spring

The spring of the discharge valve mechanism on an aero-engine were failure during servicing. The failure mode of cracks parts were investigated by using macro-observation,fracture analysis,. metallographic analysis,hydrogen content, hardness test. The results show that the failure mode of the springs is hydrogen embrittlement fracture. And the main reason of spring fracture is inhale too much hydrogen during cadmium plating process multiple corrosions.