3. Structural Changes in Austenitic-Ferritic Steel 03Kh14N10K5M2Yu2T During Heating and Cooling

As the title implies, the paper describes structural changes in a new practically carbon-free, aluminium-containing Fe-Cr-Ni-based steel. This steel has been developed for the debugging of industrial austenitic-ferritic steels (σ-phase and 475-temperature brittleness). Abnormally high microhardness of δ-ferrite, approximately equal amounts of austenite and δ-ferrite of the austenite-ferrite structure and the typical needle Widmanstatten structure of reversed austenite have been shown by magnetometric, dilatometric and microstructural studies. Recommendations are given for hot plastic deformation rates of the investigated steel. In conclusion, one can say that the steel 03Kh14N10K5M2Yu2T overcomes the drawbacks inherent to industrial duplex steels and the embrittle σ-phase is not precipitated in the steel structure in the temperature range of 1200–900 °C. The aim of this study is to investigate the solidification of δ-ferrite, an austenite-ferrite structure of the steel in the quenched state from 1000 °C, and the microhardness of δ-ferrite and reversed austenite in the austenitic-ferritic structure.