A method for determining crack opening load from load-displacement dataThe fatigue crack opening load is determined as the tangent point on the ascending load-displacement data between the curved portion and the upper linear region. A model for the 'unzipping' behavior of the crack indicates that the curved portion of the load-deflection curve is second order. The opening load is determined by a nonlinear, least squares fit of the data to the model, which optimally locates the tangent point of the two curves. The method provided consistent results for determining opening load P(op) for 7475-T731 aluminum using data from a crack tip opening gage.
Document ID
19890030042
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Carman, C. Davis (General Dynamics Corp. Fort Worth, TX, United States)
Turner, C. Christopher (General Motors Corp. Inland Div., Dayton, OH, United States)
Hillberry, Ben M. (Purdue University West Lafayette, IN, United States)