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New medium Mn steels for forged components, in combination with a new heat treatment, are presented. This new annealing process implies air-cooling after forging and austenite reversion tempering (AC + ART). This leads to energy saving compared to other heat treatments, like quenching and tempering (Q + T) or quenching and partitioning (Q + P). Furthermore, the temperature control of AC + ART is easy, which increases the applicability to forged products with large diameters. Laboratory melts distinguished by Ti, B, Mo contents have been casted and consecutively forged into semi-finished products. Mechanical properties and microstructure have been characterized for the AC and the AC + ART states. The as forged-state shows YS from 900 MPa to 1000 MPa, UTS from 1350 MPa to 1500 MPa and impact toughness from 15 J to 25 J. Through the formation of nanostructured retained metastable austenite an increase in impact toughness was achieved with values from 80 J to 100 J dependent on the chemical composition.

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A new alloy for drive‐train applications with a significant addition of vanadium is presented. The influence of vanadium addition to air‐hardening forging steels is investigated and discussed. For the investigations, a laboratory melt is casted and forged into a rod. The mechanical properties and the microstructure of the new alloy are described and compared with a vanadium‐free reference alloy from a previous study. The forged component shows high strength and hardness in the as‐forged state (YS: 892 MPa, UTS: 1366 MPa, hardness: 430 HV30) distributed equally over the full cross‐section. In addition, the strength does not decrease during subsequent heat treatments enabling the application as a material for surface treatments such as nitriding or plasma nitriding. Although strength, ductility, and hardness change as expected with increasing tempering, toughness acts different than in vanadium‐free alloys during intercritical annealing which hints at the interaction of vanadium with the fracture mechanism.

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