Hot deformation behavior of Zr–1Nb alloy: Characterization by processing map

Abstract

Hot deformation behavior of β-quenched Zr–1Nb was studied by constructing a processing map in the temperature range of 600–950 °C and strain rate range 0.002–10 s −1 . The processing map exhibited a domain of dynamic recrystallization in the temperatures range 625–800 °C and at strain rates slower than 0.1 s −1 (predominantly in the α phase) with a peak strain rate sensitivity of 0.24 occurring at 730 °C and 10 −3 s −1 , and the second domain of dynamic recovery occurring in the β phase field with its peak strain rate sensitivity of 0.22 at 950 °C and 0.1 s −1 . These domains were identified on the basis of detailed kinetic analysis , reported values of ductility and observation of deformed microstructure . While cross-slip was identified to be the dominant rate controlling mechanism during dynamic recrystallization, the rate controlling dislocation mechanism involved in dynamic recovery of the β phase was the thermally activated breaking of attractive junctions.