Salzgitter Mannesmann Forschung GmbH (Salzgitter, Germany)

Georgeou Z., Techn. Eng., Development of materials
Schöttler J., Dr. Eng., Techn. Expert, Quality steels, j.schoettler@sz.szmf.de

Institute of Metallurgy, Technical University Clausthal (Clausthal-Zellerfeld, Germany):

Rohrberg D., Mag. Math., Scientific Fellow, Metallurgical equipment workgroup
Spitzer K.-H., Prof., Dr. Eng., Chief, Metallurgical equipment workgroup
Newirkowez A., Scientific Fellow, Metallurgical equipment workgroup

Swerea Mefos (Luleå, Sweden):

Nyström R., Sr. Project Manager, Metallurgical and Environmental Dept.

Ferrous alloys using the TRIP and/or TWIP effect allow a combination of ultra-high strength and high ductility. The alloying concepts for these steels are based on a manganese content between 12 and 25% mass content. Tramp elements relevant for the production of high manganese content steels, origin and typical contents in raw material and final product are observed as well as the effect of elevated contents of tramp element on yield strength, tensile strength and total elongation of high-manganese steels. Other alloying components typically are aluminium and silicon. Mechanical properties of TRIP and TWIP steels from tensile tests are displayed on the stress-strain diagram from different alloys and in dependence between deformation to fracture and tensile strength for different materials. Mass, temperature and metal composition as a function of time are analyzed as well as slag composition as function of time and corresponding slag path in the pseudo ternary system.The presented research focusses on the assessment of economically viable process routes for the production of high manganese-content steel melts. Routes for mid- to long-term high production volume using iron-manganese-ores in a blast furnace or for direct reduction are presented. Scrap charging at Swerea Mefos 6-ton universal converter and operating of the converter during pilot trials at Swerea Mefos with slags of different basicities are discussed. Being crucial for profitability different manganese sources and alloying concepts are discussed and evaluated under the aspect of tramp elements.

1. Hofmann, H.; Menne, M.; Göklu, S.; Richter, H.: Properties of high manganese steels with induced plasti ci ty, Intern. Conf. on Steels in Cars and Trucks, Wiesbaden, 5.–10. Juni 2005.
2. Kroos, J.; Redeker, C. F.; Eichholz, H.; Spitzer, K.-H. et al.: Energiesparende Herstellung von Leichtbaustählen nach dem DSC Verfahren, Schlussbericht BMWA 0327289A, Juni 2004.
3. Gigacher, G.; Bernhard, C.; Krieger, W.: BHM 149 (2004) Nr. 3, S. 112/17.
4. Grässel, O.; Frommeyer, G.: stahl u. eisen 122 (2002) Nr. 4, S. 65/69.
5. Schäperkötter, M.; Eichholz, H.; Kroos, J.; Nieme yer, M.; Schmidt-Jürgensen, R.; Spitzer, K.-H.: Direct Strip Casting (DSC) — an option for the production of HSD steel grades, 1. intern. Conf. on Super-highstrength steels, Rom, Italien, 2.–4. Nov. 2005, ISBN 8885298567, AIM.