Kinetics of annealing of deformation defects in model alloy Zr – Sn – Fe – Cr

Abstract

The work is devoted to the study of annealing of deformation defects in the Zr – 1,4 wt. % Sn – 0,2 wt. % Fe – 0,1 wt. % Cr model alloy. The final stage of thermomechanical treatment of the alloy is cold deformation up to 25 %, heating up to 400 °C and holding at this temperature for 3 hours. The study was performed by differential scanning calorimetry (DSC) in the temperature range from room temperature to 620 – 680 °C at a heating rate of 2 – 5 °C/min. The alloy structure before and after DSC was studied by transmission electron microscopy. Two stages of annealing of deformation defects were recorded, which are interpreted as polygonization and primary recrystallization of the alloy. By the method of model kinetic analysis, it was found that the activation energy of the first stage is 127 kJ/mol, the activation energy of the second stage is 146 kJ/mol. Avrami – Erofeev equation is used as kinetic equation.