A Dynamic Failure Model for Ductile Materials
Abstract
This report presents a recently developed continuum mechanics based dynamic failure model for ductile metals. Ductile failure often initiates due to void nucleation and growth. The void generation degrades the strength and stiffness of the initially void-free material. Realistic mathematical models of this failure process requires an accurate description of the strain rate and temperature-dependent plastic flow in the intact material surrounding the microvoids. This is all the more important when the evolution law for ductile void growth is based on the plastic deformation in the intact material. An elastic perfectly plastic idealization of the intact material may lead to erroneous or sometimes limited applicability of the failure model. The present failure model incorporates a state variable based viscoplasticity theory into the model formulation. The nucleation of voids is modeled as a statistical process. A Gaussian function based on mean stress and/or strain threshold has been used in the failure model formulation. Model constants were determined for OFHC copper, Armco Iron, MAR-200, MAR-250, AF1410, C1008, and HY100 steels and tantalum. As a final exercise the ductile failure processes in different geometrical configurations were described by the RDG model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1991
- Accession Number
- ADA233600
Entities
People
- A. M. Rajendran
- D.. J. Grove
- Mark A. Dietenberger
- W. H. Cook
Organizations
- University of Dayton