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Notes: Some excellent projects have been finished successfully since the last conference on the pre-industrialstage showing the great potential of thixoforming technology for steels [1][2]. Experiments presentedin this paper on induction heating, process window and mould filling of three widely-used steel alloysoffer an even greater field of application for industrial companies.In the past thin walled cutting tools and complex impellers made of cold working steel X210CrW12were produced at the Foundry Institute [3][4]. Constitutive on this knowledge the field of applicationsis enlarged by research on two further steel alloys. Processing of 100Cr6 (roller bearing steel) and42Cr4 (annealing steel) is challenging due to a decreasing window at a higher temperature level withdecreasing carbon content.An exact procedure has been worked out to create new control programs for the induction heatingunit. It is based on thermo-chemical calculations and delivers billets with feasible temperaturedistribution and well defined content of liquid phase.Material characterization is performed in a step-die (seven steps between 25 and 0.5mm), especiallydeveloped for demands of semi-solid casting. Mould filling capacity, micro structural evolution andmechanical properties are determined on each of the seven steps.For any reproducible process the knowledge of suitable system parameters is essential. To find thelimits of the process window sensitive experimental parameters were changed systematically for eachof the three steel alloys. In addition to tool temperature the process windows consist principally ofcontent of liquid phase fs, piston velocity vP and pressure during freezing pfr. Characteristicdifferences appeared between the different steel grades.The thermal simulation was used to find functional dimensions for the gating system and to shortenprocess times. Simulation of tools system was used to estimate the additional thermal load induced byhigher working temperatures. The abrasive wear at the offsets to the next steps was in the same orderof magnitude for all examined steels.These results provide the opportunity for commercial steel grades to cast complex steel parts in highpressure die casting