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Copyright of Der Internist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Nephrologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bar extrusion process is characterised by extruding a billet through a forming die with a punch. Compared to conventional bar extrusion other tool concepts are required for semi-solid extrusion processes because forming has to take place in the semi-solid state, followed by a solidification step []. Under variations of the main process parameters like press velocity, extrusion channel length and die as well as the press channel geometry semi-solid extrusions are performed. The bars are characterised by a limited length due to insufficient solidification in the extrusion channel. Analyses concerning chemical composition, pore formation, microstructure and mechanical properties discover properties independent of the chosen process parameters. The chemical composition is constant over the bar length. It differs between globulites and eutectic. In the homogeneous microstructure few pores can be found. The determination of the mechanical properties shows a wide range of values because of the pores included in the bars. [ABSTRACT FROM AUTHOR]

This paper shows the possibility of producing demonstrating components by combining the forming operation with a simultaneous insertion of additional components. With this technology it is possible to shorten conventional process chains and to create a new generation of components. As base materials two different steel alloys are used, the low melting cold forming tool steel X210CrW12 and the bearing steel 100Cr6. As insert materials steel alloys as well as copper based alloys are considered. Consequently, the main challenges for this technology are the embedding of the inserts into the semi-solid matrix without destroying the geometry due to deforming or remelting. To characterise the produced components concerning their microstructure development and resulting material properties optical and mechanical testings were carried out. As result it could be shown that the die filling and the embedding of the inserts were feasible. The development of the microstructure of the solidified material was influenced by the geometrical conditions which also cause differences in the mechanical properties. Furthermore, there could be shown design restrictions which have to be considered in future to avoid the damaging of the inserted components. [ABSTRACT FROM AUTHOR]