The paper describes a cost effective and innovative combination of direct pressure sintering and subsequent thixoforming to produce MMC-components in (near-) net shape quality and, thus, to make these interesting materials attractive to mass production.First results of some combinations of aluminium matrix alloys with different ceramic reinforcements, consolidated by fast pressure sintering show the efficiency of this technology.The further processing of the consolidated billets has been performed by thixoforging. It can be shown, that the homogeneous microstructure from the direct pressure sintering stage with uniformly distributed ceramic reinforcements can be maintained over the semi-solid state and a full densification can be achieved. Form filling was complete and surface quality was comparable to forgings from conventional alloys.This new process flow shows advantages regarding the material yield in each of the processing steps. The (near-) net shape quality of thixoforged components allows a reduced effort for machining, which is of special importance for composite materials with a high content of wear resistant hard phases like SiC-particles.

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The following paper deals with the manufacturing of composite and hybrid materials by using semi-solid forming technologies. On the one hand, there is presented a process for producing Interpenetrating Phase Composites (IPC) consisting of ceramic open-cell structures which are infiltrated by a semi-solid aluminium alloy. On the other hand, a new process for manufacturing hybrid metallic materials is described. Thereby, semi-finished materials made of two different aluminium alloys are simultaneously heated using an induction system and subsequently formed in the semi-solid state. The paper shows numerical investigations as well as experimental results for both processes.

Current research activities at the Institute for Metal Forming Technology (IFU) of the University of Stuttgart are focusing on processing high-melting metal materials in the semi-solid state. This forming process is performed in the range between solidus and liquidus line and uses therefore the low materials viscosity in its semi-solid state for realizing complex part geometries. The research work deals with alloy systems based on titanium or cobalt which are widely used in both medical and aerospace technology. In particular, the titanium alloy Ti6Al4V, possessing high strength, low density and excellent corrosion resistance exactly matches today's lightweight aspirations, and therefore will be of greater importance in the future applications. Due to this favorable combination of properties this alloy nowadays is widely used in technical specialty areas despite its high price. Therefore, many mechanically and thermally highly stressed lightweight components such as turbine blades are designed and manufactured out of this particular titanium alloy. Conventional processes used for such material systems like casting or forging methods usually consume a lot of energy when heating the billet and require increased materials usage, which results in high production-costs. In this context the processing of such materials in the semi-solid state has a great potential in terms of producing complex net-shape or near-net-shape components with good mechanical properties.

The following paper deals with the production of Interpenetrating Phase Composites (IPC) using semi-solid forming technology. Therefore, adequate ceramic foams were selected and infiltrated by processing the aluminium alloy A356 in the semi-solid state. In the studies presented in this paper, the infiltrations of two ceramic materials (Al2O3 and SiC) with three different pore sizes (10, 20 and 30 ppi) were investigated. During the forming process the liquid phase fraction of the aluminium was varied to analyze infiltration effects in relation to the raw material´s liquid phase fraction. Afterwards, microsections of the produced specimens were analyzed in order to characterize their microstructure and the quality of infiltration. The results showed that completely filled composite components with good mechanical properties can be produced by infiltrating ceramic preforms with a semi-solid aluminium alloy.