The serrated flow and recrystallization in dispersion hardened Cu-Cr-Nb alloy during hot deformation

摘要

The hot isothermal deformation of dispersion hardened Cu-Cr-Nb alloy was studied by varying strain rate and temperature during compression testing. The compressive stress-strain curves showed oscillations in the flow stress typical of type A, type B and type C serrations which are typical of Portevin-Le Chatelier effect The serrated flow was attributed to the pinning of mobile dislocations by Cr_2Nb precipitates. The presence Cr_2Nb precipitates was also found to affect the dynamic recrystallization process during hot isothermal hot deformation.