Formulations for Rate Independent Cyclic Single Crystal Plasticity (PREPRINT)
Abstract
There is a need for accurate descriptions of the mechanical state of single crystal materials blades in gas turbine engines. These components are subject to such extreme temperatures and stresses that life prediction becomes highly inaccurate resulting in components that can only be shown to meet their requirements through experience. To help reduce this inadequacy in current design systems we have developed a thermo-viscoplastic constitutive model for single crystal materials. Our formulation additively decomposes the inelastic strain rate into components along the octahedral and cubic slip planes. Each of these is further additively decomposed into a time dependent creep component and a time independent plastic component. The strain rates are then incorporated into a large strain formulation. We formulate two robust and computationally efficient rate-independent crystal plasticity formulations. The transient variation of each of the plastic components includes a back stress for kinematic hardening and latent hardening parameters to include the increase of the stress with inelastic strain.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2010
- Accession Number
- ADA522041
Entities
People
- Alexander Staroselsky
- Brice N. Cassenti
Organizations
- Pratt & Whitney