Flow features and industrial applications of TSE rheoextrusion process

Abstract

This paper presents an overview of diverse extrusion techniques and, in particular, a focused discussion about the rheoextrusion process for semi-solid casting (a novel casting process for the fabrication of high quality metals). The review reveals a wealth of interesting rheological and microstructural features, providing qualitative and quantitative data. The analysis is supported by relevant numerical results and examples. It is shown how numerical studies can provide significant insights into these processes by providing more detailed information on the fundamental mechanisms of morphology development (during phase change) and profile forming. The die filling and solidification behaviours within extrusion dies are simulated numerically. The extrusion forming process is also investigated and compared with experimental results. The numerical results show that the profiles of velocity and solidified front of semi-solid metals (SSM) within the die will influence the final microstructure of casts, both in the interior and on the surface. Finally, an industrial application employing a special patented concept design is presented and analysed.