As the shift from the Metal Age progresses, materials engineers and materials scientists seek new analytical and design methods to create stronger and more reliable materials. Based on extensive research and developmental work done at the author’s multi-disciplinary material laboratory, this graduate-level and professional reference addresses the relationship between fracture mechanisms (macroscale) and the microscopic, with the goal of explaining macroscopic fracture behavior based on a microscopic fracture mechanism. A careful fusion of mechanics and materials science, this text and monograph systematically considers an array of materials, from metals through ceramics and polymers, and demonstrates lab-tested strategies to develop desirable high-temperature materials for technological applications.

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 Memorandum discusses the current situation on the inclusion of fracture-toughness testing requirements in specifications for high-strength steels used for military applications. The Memorandum was prepared at the request of The Technical Cooperation Program (TTCP), and contains information from Canadian and British members of that program, as well as U.S. information. Military applications discussed include missile motor cases, aircraft landing gear, gun tubes, armor plate, and hydrofoils. (Author).