Thixoforming of Steels – A Status Report

The thixoforming of metals is a new forming technology, which combines the advantages of casting and forging and focuses on the production of structural components with complex shapes. Various components made of aluminium and magnesium are already industrially produced. Apart from this, using steels in the thixoforming processes is still a matter of research. This paper summarises the state of the art of steel thixoforming. Besides relevant material and process parameters, different process routes, numerical modelling techniques, and tool requirements are discussed. In addition, thixoformed prototypes of different steel grades are presented and evaluated with defect index cards, which characterise occurring defects and give suggestions how to avoid them. The design of suitable tool materials and tool concepts, the development of heating strategies which provide a homogeneous temperature distribution, and the development of thixoformable steels are main topics of current research. This paper focuses on the technology of steel thixoforming with regard to the material requirements, the production processes, and the accompanying current technical problems.

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