Fracture-toughness testing using principles of fracture mechanics has developed to the point where it can be used as a basis for selection of materials, for estimating limiting design stresses assuming the presence of small flaws, and for analyzing failures. Current methods of measuring plane-stress and plane-strain fracturetoughness parameters are presented in this report. The specimens include center-cracked, edge-cracked, single-edge-cracked, surface-cracked, and notched round bars, which are subjected to tensile loading, and notched bars for bend tests. The different types of specimens permit evaluating sheet, plate, bar stock, and forgings as well as material from failed structures. Application of fracture-toughness parameters to design of high-strength structures is reviewed for both static and fatigue loading. Consideration of the fracture-mechanics concepts in design should lead to fewer problems with brittle fracture in high-strength structures. (Author).

The report contains the first compilation of available Plane-strain fracture toughness data and is the result of considerable interest during the past few years in developing test methods for obtaining these data. The report is divided into sections on aluminum alloys, high-strength alloy steels, intermediate- and low-strength steels, precipitation-hardening stainless steels, titanium alloys, nickel-base alloy 718, and beryllium.