Modelling and Simulation of Phase Formations in Martensitic Stainless Steels

Modelling and simulation of solidification processes and solid-state phase transformation have become key instruments in the field of alloy development and heat treatment optimization. Apart from equilibrium-controlled processes, also diffusion-based effects need to be considered. This contribution presents some typical approaches at the example of martensitic stainless steels. Important aspects affecting the production and properties of these steels, such as alloying limits with nitrogen, the formation of ledeburitic structures, or the retained austenite content after heat treatment, can be predicted with reasonable accuracy.

Thermo-Physical Parameters Determination of Nano-Crystalline Fe72.5Cu1Nb2Mo1.5Si14B9 Alloy for Twisted Magnetic Cores Heat Treatment Optimization

Thermophysical parameters of Finemet-type initially amorphous alloy produced using rapid quenching technique were determined. The temperature intervals of phase and structure changes have been obtained using calorimetry and non-ambient X-ray diffraction methods. The electric resistance data were recalculated to alloy electrical conductivity which it was recalculated to heat conductivity using the Wiedemann–Franz law. Resulting parameters were used for heat processes simulation that occurs in amorphous material of built-up transformer core during annealing in nanocrystallization temperature interval. Heat treatment of different sizes twisted magnetic cores was optimized.