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Notes: This work describes the processing of different aluminum cast- and wrought alloys in theCooling-Channel-Process. The investigations take the castability, the microstructural evolution forthe SSM-processing and the resulting properties in the test specimen into account. Beside the alloysAlMg5Si2Mn (M59), AlCu4TiMgAg (AF48), AlSi12CuNiMg (SF70), AlSi17Cu4Mg (SF90),AlZnMgCu1,5 (AA7075) the optimization of the alloy AlSi7Mg0,3 (A356) by the addition ofmagnesium and copper were a main task of the work

Notes: Alloys of a specific microstructure exhibit a shear-rate history-dependent flow behaviour in thesemi-solid state. Rheological studies have been carried out using various experimental techniquessuch as concentric cylinder rheometers of Couette or Searle type as well as capillary rheometers andparallel plate compression tests. With the Searle type rheometer and the capillary rheometer twodifferent approaches of rheological measurement techniques are discussed and compared regardingadvantages, potentials and its distinct characteristics.Experiments using the Searle type rheometer have been conducted under steady-state or oscillatingconditions and have been used to verify time-dependency of step responses due to discontinuous orlinear variances of the shear rate. These experiments provide all types of flow curve parameters asimplemented in the numerical simulation. However the variances of the commonly used Couette andSearle type rheometers are limited to shear-rates which are significantly lower than that appearing inthe technical thixo- or rheocasting processes. For that reason an additional experimental set-up with ahorizontal slot capillary integrated in a shot-controlled high-pressure die-casting machine is used inorder to examine flow properties at shear rate conditions similar to those in real thixocastingprocesses.After an initial examination of low temperature model alloys, such as PbSn15, the experimentalset-up is then adjusted in order to obtain rheological data for light metal alloys such as AluminiumAlSi7Mg0.3. The Aluminium alloy is processed within each rheometer either as partially solidified orpartially remelted in order to represent conditions of both, the conventional thixocasting and the latelyintroduced rheocasting process. Finally the appearance of physical phenomena which affects theaccuracy of rheological experiments such as wall slip is considered for both types of rheometers

Notes: This investigation describes the development and evaluation of thixoformable alloys onAl-Li-Mg basis in the scope of the collaborative research center SFB 289 at RWTH AachenUniversity. Scandium and zirconium was added to Al-Li2.1-Mg5.5 (A1420) with the aid of DoE(Design of Experiments) and precursor billets were manufactured by pressure induction melting(PIM). To evaluate the thixoformability of the synthesized alloys high-quality semi solid processeddemonstrators were manufactured by the Rheo-Container-Process. Subsequent heat treatment raisedthe mechanical properties to maximum values of tensile strength of 432MPa, yield strength of220MPa and an elongation of 13%. The RCP-Process was designed for the special requirements ofthis high reactive alloy. The paper will present extraordinary benefits in terms of properties andprocess simpleness for the semi-solid processing of Al-Li alloys

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

Notes: The semi solid forming of steel has the potential of an innovative technology, which couldopen a new possibility of metal components production. Earlier research works in the 1990s havealready shown the principal feasibility of the process but also revealed the various kinds of technicalproblems. Since then, research works on steel processing have been continuously made in severallocations in Japan, USA and Europe. Currently, the focus of these research activities is thedevelopment of suitable tool material and the achievement of high part quality, which is the key pointfor the success of the process. This paper gives an overview of the previous research works and thecurrent state of the research with an outlook on future tasks for this challenge

Notes: Semi-solid forming offers new potentials for processing of high reactive and hot cracksusceptible aluminium-lithium wrought alloys. With the tailored alloy AA1420* (AlLi2.1Mg5.5+Sc+Zr) a promising material for thixoforming with achievable high strength of up to 500MPatensile strength and over 400MPa yield strength concomitant with its low density of 2,46g/cm3 isachievable. Due to high solid fractions the effect of solidification shrinkage could be sufficientlydecreased with the result of hot-tear-free casting.Simulation supported a critical to cast automotive tie rod was exemplarily manufactured via semisolid-technology with promising results.Furthermore with an improved and advanced heat treatment enhanced mechanical properties,comparable to those of rolled AA1420, were achieved