Thin Slab Casting and Rolling processes provide a highly efficient method for producing hot rolled strip. Nowadays a wide range of alloys is already manufactured this way. Next to Advanced High Strength Steels (AHSS) such as dual phase steels, there is a high interest in fabricating Transformation Induced Plasticity (TRIP) steels because of their superior mechanical properties. Due to the high content of Silicon and Aluminum, difficulties in case of casting and rolling are expected. Aim of this thesis is the analysis of the high temperature oxidation and the phase transformation behavior with regard on continuous casting and rolling conditions. Therefor methods for simultaneous thermal analysis (STA) and in-situ characterization of phase transformations by using a high temperature laser scanning confocal microscope (HT-LSCM) are optimized. Both methods show superior potential with regard on these tasks. The properties of four different alloys with different Al- and Si-contents are determined. The results indicate that process parameters have to be optimized separately for each alloying composition or vice versa the alloy must be adapted to the manufacturing conditions. As well as in case of heat treatment as in regard of surface oxidation Al-Si-Mix-concepts seem to provide the best potential for industrial production in future compared to pure Si- or Al-types. Thin Slab Casting leads to very high cooling rates. Therefor the absolute oxidation amount is rather low which should be beneficial concerning following processing steps. The adjustment of a TRIP microstructure is even at the short cooling times at continuous casting and rolling plants possible.
|Translated title of the contribution||Investigations on the Behavior of AHSS Alloys in Endless Strip Casting Processes|
|Publication status||Published - 2020|
Bibliographical noteembargoed until null
- High Temperature Oxidation
- Thin Slab Casting