Some Results on the Dynamic Deformation of Copper
The influence of strain rate and strain rate history on the mechanical behaviour of copper single crystals has been studied by means of compression tests. The shear strain rate range 10-4s-1–8 103s-1 has been investigated. Dynamic tests were performed with an Hopkins on bar.
The strain rate behaviour can be divided into 2 regions. Above 103s-1 a linear relationship between shear stress and shear strain rates is observed. This can be explained by a viscous damping of dislocations. Static curves are sometimes over the dynamic ones depending of the strain rate.
Tests performed with change of strain rate have shown that strain rate history memory is never lost.
Results are compared with those obtained by tensile tests.
KeywordsHigh Strain Rate Shear Strain Rate Strain Rate Effect Copper Single Crystal Dynamic Shear Stress
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