Semi-solid forming of non axis-symmetric parts from steel grade X210CrW12 with PVD coated tools

Semi-solid forming of steels has the potential to produce components with good mechanical properties and complicated geometry from high strength steels due to the advantages of forging and casting processes combination. Due to the high process temperatures thixoforging of steels has to meet high demands on process parameters accuracy and control. The thixoforging process parameters like billet temperature, temperature distribution after the reheating, Argon gas pressure, transportation time and forging load were experimentally investigated on thixoforging of a non axis-symmetric 4 kg demonstrator part of steel grade X210CrW12. Due to the high process temperatures, thermal and mechanical loads the development of a suitable tool concept is necessary. Hardened hot working steel X38CrMoV5-1 as a tool bulk material with protecting thin film crystalline (Ti,Al)N/γ-Al2O3 deposited by means of Physical Vapour Deposition (PVD) showed good results in first experimental series. The Scanning Electron Microscope images show mechanical damage of the tool radii edge while the rest tool surface look intact after 170 thixoforging cycles.