Unified constitutive material models for nonlinear finite-element structural analysisUnified constitutive material models were developed for structural analyses of aircraft gas turbine engine components with particular application to isotropic materials used for high-pressure stage turbine blades and vanes. Forms or combinations of models independently proposed by Bodner and Walker were considered. These theories combine time-dependent and time-independent aspects of inelasticity into a continuous spectrum of behavior. This is in sharp contrast to previous classical approaches that partition inelastic strain into uncoupled plastic and creep components. Predicted stress-strain responses from these models were evaluated against monotonic and cyclic test results for uniaxial specimens of two cast nickel-base alloys, B1900+Hf and Rene 80. Previously obtained tension-torsion test results for Hastelloy X alloy were used to evaluate multiaxial stress-strain cycle predictions. The unified models, as well as appropriate algorithms for integrating the constitutive equations, were implemented in finite-element computer codes.
Document ID
19850057618
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Kaufman, A. (NASA Lewis Research Center Cleveland, OH, United States)
Laflen, J. H. (General Electric Co. Cincinnati, OH, United States)
Lindholm, U. S. (Southwest Research Institute San Antonio, TX, United States)