Prediction of Propagation for Surface Crack

Fracture damage usually occurs from pre-existing defects or small cracks in service. The fatigue cracks of structural parts mostly start on the surface and expand under the action of fatigue load, which leads to the failure of structural parts in engineering. The initiating and propagation analysis of surface crack is critical for structural integrity prediction of cylindrical metallic components with circular cross section, since these components have been applied widely in engineering.This book is a collection of research methods for predicting surface crack growth. The crack growth circles method is developed for the surface cracks of a round bar subjected to tension and torsion loads. A multiparameter model with fewer shape restraints whose center is allowed to move arbitrarily is built, and the shape change of a fatigue crack is predicted more precisely.