Hot deformation characteristics and kinetics analysis for Nickel-based corrosion resistant alloy

Abstract

The hot deformation characteristics of Nickel-based corrosion resistant alloy was studied in the temperature range of 1050˜1200oC and the strain rate range of 0.001˜0.1s-1 by employing hot compression tests. The results show that the peak stress increases with decreasing temperature and increasing strain rate, and the activation energy is about 409kJ/mol. Basing on the Avrami equation through using the critical strain (εc) and the strain for 50% DRX (ε0.5), a kinetic model for dynamic recrystallization (DRX) was established, where the model parameters could be obtained using the modified Zener-Hollomon parameter (Z*). Applying the model, the predicted value of the steady state strain (εss) and the strain for maximum softening rate (εm) agree well with the experimental results. Accordingly, the relationship between ε m and ε 0.5 is established, which is mainly dependent on the Avrami exponent (n). When n <3.25, εm becomes less than ε0.5 and the difference in between decreases with increasing the strain rate or decreasing the deformation temperature. Finally, through observing DRX microstructure under different deformation conditions, a power law relation between DRX grain size (Ddrx) and Z*, with an exponent of-0.36, was found.

Numerical Simulation of Segregation in Slabs under Different Secondary Cooling Electromagnetic Stirring Modes

“…The development of steel slab varieties has raised the bar for internal quality standards, particularly emphasizing the homogenization of elemental composition and the refinement of the solidification microstructure [1,2]. However, challenges persist in the production process, such as inadequate isometric crystallinity rates in cast billets and severe segregation of alloying elements, which lead to a diminished steel toughness and plasticity, as well as inconsistent mechanical properties.…”