Transformation-induced plasticity in Fe–Cr–V–C

On the basis of the Fe_84.3C_4.6Cr_4.3Mo_4.6V_2.2 high-speed tool steel, manufactured under relatively high cooling rates and highly pure conditions, a further improvement of the mechanical characteristics by slight modification of the alloy composition was attempted. For this, the alloy Fe_88.9Cr_4.3V_2.2C_4.6 was generated by elimination of Mo. By applying special preparation conditions, a microstructure composed of martensite, retained austenite, and a fine network of special carbides was obtained already in the as-cast state. This material exhibits extremely high compression strength of over 5000 MPa combined with large compression strain of more than 25% due to deformation-induced martensite formation. With this alloy a new composition of transformation-induced plasticity-assisted steels was found, which shows an extreme mechanical loading capacity.