Innovative technological processes can help us to obtain unconventional structures with specific mechanical properties, even from conventional materials. Forming metal alloys in the semi-solid state is one of many ways. With thixoforming the tool steel X210Cr12 was treated with rapid solidification from the liquid phase. The microstructure after processing in the semi-solid state is 96% globular austenite formations surrounded by a carbide network. The aim of the experiment was to test the new technological process and to describe the obtained microstructure and its stability. The stability of the microstructure was tested under various thermal constraints and mechanical loading. The hardness of the austenite component after thixoforming was about 320 HV 0.05; hardness of the carbide network was about 550 HV 0.05.