Continuous and interrupted room temperature compression tests were carried out on geometrically similar specimens of duralumin, pure copper and lead, using steel and ebonite dies. Significant differences in strain-hardening rate were ascribed to heat-transfer during deformation. It was concluded that the yield-stress is strongly sensitive to small changes in temperature occurring during deformation. It is suggested that the time dependence of the associated recovery processes is the origin of the strain-rate effect.
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