Failure analysis of an automobile valve spring

Abstract This paper presents the failure analysis of an automobile valve spring which failed in service. The fractured surfaces as well as the surface of the spring material close to the fractured surface were examined in a scanning electron microscope at suitable magnifications. Optical microscopy was performed to evaluate the basic microstructure of the as-received material. Detailed electron microscopic studies have indicated that the failure was due to the presence of non-metallic inclusions near the surface of the spring material.