A new form of a unified viscoplastic material model basedon verstress was implemented in finite element code using a material constitutive equation programme. The analysis results, employing equivalent forms of the stresses, the overstresses and the inelastic strains, were consistent with results obtained from: (i) uniaxial dircet rate dependent integration simulations, (ii) results obtained indirectly by employing experimental stress strain cuves and, (iii) experiments. Simulations of two batches of C- (commercial purity) titanium specimens conaining cracks subjected ot either different displacement rates, or sustained loads (creep) predicted material deformation and failure behaviour that was close to experimental results. However, the simulation results were dependent on material constants that were difficult to determine experimentally.
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