Large Deformation Plasticity of Polycrystalline Tantalum

Abstract

A physical, crystal mechanics-based theory of thermo-elasto-viscoplasticity which is valid for large strains and high strain rates at low homologous temperatures has been formulated. The theory is able to predict the macroscopic anisotropic stress-strain response, the evolution of crystallographic texture, and the macroscopic shape changes for b.c.c. tantalum. The material functions and parameters in the model were determined by calibrating the model against existing experimental results for tantalum. The model reproduces the data of these researchers rather well. The constitutive model has been implemented in the finite element program ABAQUS Explicit by writing a 'user material' subroutine. The ability of the constitutive model and computational procedures to capture the effect of initial texture on the final shape under high strain rates and large strains was evaluated by carrying out a simulation of a Taylor rod-impact experiment and by comparing the predicted final shape to that observed experimentally.

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Document Details

Document Type
Technical Report
Publication Date
Dec 21, 2000
Accession Number
ADA385746

Entities

People

  • Lallit Anand

Organizations

  • Massachusetts Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Constitutive Equations
  • Crystal Structure
  • Crystals
  • Elements
  • Explosively Formed Penetrators
  • Materials
  • Materials Engineering
  • Mechanics
  • Metals
  • Personal Information Managers
  • Plastic Properties
  • Polycrystals
  • Simulations
  • Single Crystals
  • Strain Rate
  • Stress Strain Relations
  • Tantalum

Readers

  • Computational Modeling and Simulation
  • Materials Science and Engineering.
  • Mechanical Engineering/Mechanics of Materials.