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Download or read book Experimental and Theoretical Determination of J(1C) for 2024-T351 Aluminum Alloy written by P. W. Beaver and published by . This book was released on 1986 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of linear elastic fracture mechanics (LEFM) to many practical situations is inappropriate because of crack initiation and growth are usually accompanied by crack tip plasticity. As a result, considerable effort has been devoted to developing methods to characterize the fracture properties of metals in the elastic-plastic regime. The integral, as initially proposed by Rice, is one elastic plastic fracture mechanics parameter which has aroused considerable interest in recent years. It can be regarded as a measure of the intensity of the crack tip plastics stress and strain fields. Begley and Landes first proposed that the onset of crack extension under plane strain conditions would occur when the integral exceeds a critical value JIC. Since then considerable data have been published supporting the use of JIC as an elastic-plastic fracture criterion. This paper describes a test program to determine the JIC value for an extruded medium-strength alloy, 2024-T351, which is used in the aircraft industry. This value was determined using: (i) the Hutchinson Rice-Rosengren crack tip model and experimentally-determined crack tip strain profiles, (ii) a finite element-hybrid contour method, (iii) a modified linear elastic method, and (iv) the multiple and single specimen methods, as described in the ASTM standard E-813-81.