Abstract The processing of metals in the semi-solid state (thixoforming) promises to enlarge the spectrum of application for various metals. Compared to casting the quality of the final product can be improved, as less defects related to solidification processes occur. Compared to forging processes, the needed forming loads are lower and more complexly shaped parts can be produced net or near-net in a one step process. On the basis of its outstanding mechanical properties that can be adjusted by adequate heat treatments, steel possesses possibilities for light weight constructions realisable by complex shapes. The semi-solid processing of steels is one focal point at the Institute for Metal Forming (IBF). Thixoforming experiments are carried out to investigate the feasibility of different steel grades. The heating of billets into the forming temperature and the forming operation itself takes place within a protective gas atmosphere to avoid the growth of scale on the billet’s surface. To study the applicability of different tool materials the die halves are built up out of segments. Theoretical approaches to predict the suitability of different steel grades for semi-solid processing especially concerning the width of a process window for thixotropic flow behaviour are presented. Furthermore the results of forming experiments regarding chemical homogeneity and mechanical properties of the thixoformed parts are pointed out. Since first forming experiments using conventional hot working tool steel as die material have shown massive wear and plastic deformation, tailored dies have been developed. The supply of suitable die concepts is one major task to ensure the cost effectiveness of this technology. One major potential of the semi-solid technology in the future may be the combination of the processes forming and joining taking advantage of the high flowability of semi-solid materials. This approach will lead to new possibilities for production of functionally integrated parts leading to new component classes and minimising assembly costs. In this paper results of joining functional steel parts (screw) with a steel component during thixoforming in a one step process are presented.