Role of electro-discharge machining on the fatigue performance of 15–5PH stainless steel component

Precipitation hardened stainless steel of 15–5PH grade is used for fabrication of actuator components. During one of the qualification tests, a piston made of this steel was fractured under cyclic loading. Analysis revealed that fracture initiated at the electro-discharge machined surface and propagated under cyclic loading.Efforts were made to establish role of various parameters of electro-discharge machining to the fatigue performance of the material.This paper brings out the details of investigation and suggests remedial measures to improve performance of material under fatigue.