Dislocation impediment by the grain boundaries in polycrystals

Thermodynamic dislocation theory incorporating dislocation impediment by the grain boundaries is developed to analyze the shear test of polycrystals. With a small set of physics-based material parameters, we are able to simulate the stress-strain curves for the load and its reversal, which are consistent with the experimental curves of Thuillier and Manach (Int J Plast 25:733-751, 2009). Representative distributions of plastic slip under load and its reversal are presented, and their evolution explains the extended length of the transition stage during load reversal.

Automated summary

The thermodynamic dislocation theory incorporating dislocation impediment by grain boundaries was developed to analyze shear tests on polycrystals, successfully simulating stress-strain curves consistent with experimental data. Representative distributions of plastic slip were presented, explaining the extended transition stage during load reversal.