EUROPEAN STEEL TECHNOLOGY AND APPLICATION DAYS 2017 - ESTAD 2017

Hot work tool steels have been developed, employing combined precipitation of carbides and intermetallic particles. Synergistic precipitation hardening effects were used to reduce the necessary carbide content. An appropriate minimum of nickel and aluminium additions were determined to precipitate intermetallic NiAl particles, maintaining the materials characteristics. Material and technological properties on tempering behavior, impact toughness, isothermal tempering resistance and thermal conductivity were evaluated. Microstructure analysis using transmission electron microscopy (TEM) reveals the existence of NiAl-rich particles in the overaged condition. Atom probe tomography (APT) proof the coexistence of nm-sized NiAl particles and Mo-rich carbides in the quenched and tempered state. First results on thermal-shock resistance of homogenized industrial material are promising. Overall, attractive material properties, combined with resource efficiency and low costs were obtained by the use of intermetallic NiAl particles, compensating carbide forming elements.