Segregation Behaviour of Third Generation Advanced High-Strength Mn-Al Steels
The paper addresses the macro- and microsegregation of alloying elements in the new-developed Mn-Al TRIP steels, which belong to the third generation of advanced high-strength steels (AHSS) used in the automotive industry. The segregation behaviour both in the as-cast state and after hot forging was assessed in the macro scale by OES and by EDS measurements in different structural constituents. The structural investigations were carried out using light and scanning electron microscopy. A special attention was paid to the effect of Nb microaddition on the structure and the segregation of alloying elements. The tendency of Mn and Al to macrosegregation was found. It is difficult to remove in Nb-free steels. Microsegregation of Mn and Al between austenite and ferritic structural constituents can be removed.
De Moor E., Gibbs P. J., Speer J. G., Matlock D. K. (2010). Strategies for third-generation advanced high-strength steel development. Iron and Steel Technology. 7/11, 133-144.
Merwin M. J. (2008). Microstructure and properties of cold rolled and annealed low-carbon manganese TRIP steels. Iron and Steel Technology. 5/10, 66-84.
Kim S. J. (2010). Effects of manganese content and heat treatment condition on mechanical properties and microstructure of fine-grained low-carbon TRIP-aided steels. Materials Science Forum. 638-642, 3313-3318.
De Cooman B. C., Lee S., Kumar S.S (2010). Ultra-fine grained manganese TRIP steel. Proc. of 2nd Inter. Conf. "Super-High Strength Steels", Peschiera del Garda, 1-11 (CD-ROM).
Grajcar A., Kuziak R. (2011). Softening kinetics in Nb-microalloyed TRIP steels with increased Mn content. Advanced Materials Research. 314-316, 119-122.
Pichler A., Traint S., Hebesberger T.,. Stiaszny P, Werner E. A. (2007). Processing of thin multiphase steel grades. Steel Research International. 78, 216-223.
Wietbrock B.,. Bambach M, Seuren S.,. Hirt G. (2010). Homogenization strategy and material characterization of high-manganese TRIP and TWIP steels. Materials Science Forum. 638-642, 3134-3139.
Grajcar A., Kalinowska-Ozgowicz E., Opiela M., Lesz S. (2011). Microstructural characterization of novel increased-manganese content TRIP steels. Proc. of the 20th Inter. Conf. "METAL'2011", Brno. 1-6 (CD-ROM).
Grajcar A., Kalinowska-Ozgowicz E., Opiela M., Grzegorczyk B., Gołombek K. (2011). Effects of Mn and Nb on the macro- and microsegregation in high-Mn high-Al content TRIP steels. Archives of Materials Science and Engineering. 49/1, 5-14.
Bhattacharya D. (2011). Perspectives on coated advanced high strength steels for automotive applications, Proc. of the 8th Inter. Conf. "GALVATECH'2011", Genova. 3-11.
Zajac S., Schwinn V., Tacke K. H. (2005). Characterisation and quantification of complex bainitic microstructures in high and ultra-high strength linepipe steels. Materials Science Forum. 500-501, 387-394.