Theoretical and experimental comparisons of the nonlinear energy method to the J-integral, R-curve and COD methods in fracture toughness testingBecause of the current high degree of interest in the development of a standard nonlinear test method, analytical and experimental comparisons have been made between the R-curve, COD, J-integral and nonlinear energy methods. A general definition of fracture toughness is proposed and the fundamental definitions of each method are compared to it. Experimental comparisons between the COD, J-integral, nonlinear energy and standard ASTM methods have been made for a series of compact tension tests on several aluminum alloys. Some of the tests were conducted according to the ASTM standard method E399-72, while the specimen thickness was reduced below the minimum requirement for plane strain fracture toughness testing for several other test series. The fracture toughness values obtained by the COD method were significantly higher than the toughness values obtained by the other three methods. All of the methods displayed a tendency to yield higher toughness values as the thickness was decreased below the ASTM plane strain requirement.
Document ID
19750045430
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Liebowitz, H.
Jones, D. L.
Poulose, P. K. (George Washington University Washington, D.C., United States)
Date Acquired
August 8, 2013
Publication Date
January 1, 1974
Subject Category
Metallic Materials
Meeting Information
Meeting: Mechanical behavior of materials; Symposium