Effect of strain rate on crack growth in aluminum alloy 1100-0

Stress and damage analysis are performed to analyze the Mode I crack growth behavior of a central crack panel made of aluminum alloy 1100-0. On account of the highly nonhomogeneous stress state, each material element would experience a different strain rate depending on the location and loading rate. A data bank of uniaxial stress and strain curves is provided to cover the range local strain rates depending on the load time history. Such a approach is referred to as the strain rate dependent model in contrast to plasticity that utilizes a single constitutive relation. The strain energy density criterion is applied to determine the onset of crack initiation, stable crack growth and final termination. A unique feature of the approach is that the same criterion could describe the foregoing three distinct events of fracture behavior. Results are obtained for applied loads with different strain rates and compared with those obtained from the classical theory of plasticity, which is unconservative. (C) 1999 Elsevier Science B.V. All rights reserved.