The process of fatigue failure consists of three stages: initial fatigue damage leading to crack initiation; crack propagation to some critical size; and final, sudden fracture of the remaining cross section. Variations in mechanical properties, composition, microstructure, and macrostructure, along with their subsequent effects on fatigue life, have been studied extensively to aid in the appropriate selection of steel to meet specific end-use requirements. The metallurgical variables having the most pronounced effects on the fatigue behavior of carbon and low-alloy steels are strength, ductility, cleanliness, residual stresses, surface conditions, and aggressive environments. The article discusses the stress-based and strain-based approach to fatigue. The application of fatigue data in engineering design is complicated by the characteristic scatter of fatigue data; variations in surface conditions of actual parts; variations in manufacturing processes such as bending, forming, and welding; and the uncertainty of environmental and loading conditions in service.
ASM Reference Publications Catalog
The Fall / Winter 2019-2020 Catalog features more than 200 products including new and upcoming releases, popular best sellers, digital databases, and journals. Save now with set sales.