Precipitation strengthening in titanium-stabilized austenitic stainless steels can improve the hot yield strength, as requested, e.g., for nuclear industry applications. The resulting properties depend mainly on the parameters of the heat treatment and previous forming. The influence of the heat treatment parameters on the development of the microstructure and mechanical properties was determined for steel 08Ch18N10T (GOST). Solution annealing and stabilization with different temperatures and holds were performed on the steel, which was, in delivered condition, stabilized at 720 °C. Heat-treated samples were subjected to static tensile testing at room temperature and at 350 °C, microstructural analysis using light, scanning electron and transmission electron microscopy focused on precipitates, and HV10 hardness testing. The strengthening mechanism and its dependence on the stabilization parameters are described. The results of the experiment show the influence of the state of the input material on the final effect of heat treatment—repeated heat treatment achieved lower-strength characteristics than the initial state, while almost all modes showed above-limit values for the mechanical properties. Stabilization temperatures of 720 to 800 °C were found to be optimal in terms of the achieved hot yield strength. At higher temperatures, slightly lower strengths were achieved, but at significantly shorter dwell times.

Medium manganese steels fall into the category of modern third-generation high-strength steels. Thanks to their alloying, they use a number of strengthening mechanisms, such as the TRIP and TWIP effects, to achieve their mechanical properties. The excellent combination of strength and ductility also makes them suitable for safety components in car shells, such as side reinforcements. Medium manganese steel with 0.2% C, 5% Mn, and 3% Al was used for the experimental program. Sheets with a thickness of 1.8 mm without surface treatment were formed in a press hardening tool. Side reinforcements require various mechanical properties in different parts. The change in mechanical properties was tested on the produced profiles. The changes in the tested regions were produced by local heating to an intercritical region. These results were compared with classically annealed specimens in a furnace. In the case of tool hardening, strength limits were over 1450 MPa with a ductility of about 15%.

Medium manganese steels belong to the group of third generation high-strength steels. These steels show an excellent combination of strength and ductility. Their manganese content ranges from 3 to 12%. After hot forming, the structure is usually martensitic. During intercritical annealing, martensite partly transforms to austenite. The choice of the correct alloying and intercritical annealing parameters, especially the heating temperature, leads to sufficiently stable retained austenite, which significantly affects the mechanical properties. The retained austenite exhibits TRIP effect during cold deformation and contributes to a significant deformation strengthening of the material.Medium manganese steel with 0.2% C, 5% Mn and 3% Al was subjected to various intercritical annealing regimes after hot forming. To increase the stability of the retained austenite, isothermal hold at different temperatures was performed in the bainitic transformation region. To verify the effect of deformation, incremental deformation was applied during cooling. After processing, martensitic structures were obtained with varying fractions of bainite, ferrite and retained austenite. The ultimate tensile strength up to 1940 MPa was reached and the elongation was about 10%.

This paper presents a thermal analysis of clamping jaws for a thermomechanical simulator, which is compared with the results from a thermal camera and thermocouples placed directly on the specimens during experimental testing. The clamping jaws have several cooling circuits inside of them and are actively cooled throughout the process. The test specimens are in turn heated by high-frequency electrical resistance heating. During the testing, it was observed whether the cooling system is sufficient, partly because polymeric materials are also used on the jaws to electrically insulate the system. Based on the measurements, it was found that even though the test specimen is heated almost to 1000 °C for a long time, the temperature of the jaws does not exceed 40 °C. The suitability of the proposed cooling system was proved and also the satisfactory agreement of experimental measurements with numerical simulations was achieved.