The influence of the pre-annealing on Mn partitioning behavior was investigated for hot-rolled Fe–0.095C–6.93Mn–1Al–1.07Si medium-Mn-TRIP steel. Unlike the fully martensitic microstructure before one-step intercritical annealing, a mixed microstructure of preexisting ferrite, austenite and martensite was obtained prior to the final annealing in two-step annealed steels. The microstructure observation showed that lath-type austenite existed in the martensitic matrix, blocky and granular austenite occurred at the boundaries of primary austenite/preexisting ferrite or martensite/preexisting ferrite after two-step annealing. Based on the numerical simulations of the second annealing process, the preexisting austenite further grew rapidly without nucleation, while some secondary austenite nucleated at the martensitic lath boundaries and then grew into martensite at a relatively sluggish rate. Moreover, significant Mn partitioning with a special “bimodal distribution” feature was detected in the preexisting austenite, resulting in the formation of martensite/austenite constituents. Compared with the case of one-step heat treatment, an excellent combination of strength (1145 MPa) and ductility (39%) was obtained in the steel with pre-annealing, which was ascribed to the occurrence of martensite/austenite islands and positive TRIP effect over a wide strain range.
This is a preview of subscription content, log in to check access.
Buy single article
Instant unlimited access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Han J, Lee SJ, Jung JG, Lee YK (2014) The effects of the initial martensite microstructure on the microstructure and tensile properties of intercritically annealed Fe–9Mn–0.05C steel. Acta Mater 78:369–377
Aydin H, Essadiqi E, Jung IH, Yue S (2013) Development of 3rd generation AHSS with medium Mn content alloying compositions. Mater Sci Eng, A 564:501–508
Bouaziz O, Zurob H, Huang M (2013) Driving force and logic of development of advanced high strength steels for automotive applications. Steel Res Int 84:937–947
Lee YK, Han J (2015) Current opinion in medium manganese steel. Mater Sci Technol 31:843–856
Suh DW, Kim SJ (2017) Medium Mn transformation-induced plasticity steels: Recent progress and challenges. Scr Mater 126:63–67
Liu H, Sun H, Liu B, Li D, Sun F, Jin X (2015) An ultrahigh strength steel with ultrafine-grained microstructure produced through intercritical deformation and partitioning process. Mater Des 83:760–767
Tekeli S, Güral A (2007) Effect of intercritical annealing and quenching plus tempering heat treatments on microstructure of Ni added powder metallurgy steels. Mater Des 28:1353–1357
Yang F, Luo H, Hu C, Pu E, Dong H (2016) Effects of intercritical annealing process on microstructures and tensile properties of cold-rolled 7Mn steel. Mater Sci Eng, A 685:115–122
Cai ZH, Ding H, Misra RDK, Ying ZY (2015) Austenite stability and deformation behavior in a cold-rolled transformation-induced plasticity steel with medium manganese content. Acta Mater 84:229–236
Ryu JH, Kim JI, Kim HS, Oh CS, Bhadeshia HKDH, Suh DW (2015) Austenite stability and heterogeneous deformation in fine-grained transformation-induced plasticity-assisted steel. Scr Mater 68:933–936
Gibbs PJ, Moor ED, Merwin MJ, Clausen B, Speer JG, Matlock DK (2011) Austenite stability effects on tensile behavior of manganese enriched austenite transformation-induced plasticity steel. Metal Mater Trans Part A 42:3691–3702
Lee S, Lee SJ, Cooman BCD (2011) Austenite stability of ultrafine-grained transformation-induced plasticity steel with Mn partitioning. Scr Mater 65:225–228
Zou Y, Xu YB, Hu ZP, Gu XL, Peng F, Tan XD et al (2016) Austenite stability and its effect on the toughness of a high strength ultra-low carbon medium manganese steel plate. Mater Sci Eng, A 675:153–163
Xu YB, Zou Y, Hu ZP, Han DT, Chen SQ, Misra RDK (2017) Correlation between deformation behavior and austenite characteristics in a Mn–Al type TRIP steel. Mater Sci Eng, A 698:126–135
Zhu J, Ding R, He J, Yang Z, Zhang C, Chen H (2017) A cyclic austenite reversion treatment for stabilizing austenite in the medium manganese steels. Scr Mater 136:6–10
Xie ZJ, Shang CJ, Subramanian SV, Ma XP, Misra RDK (2017) Atom probe tomography and numerical study of austenite stabilization in a low carbon low alloy steel processed by two-step intercritical heat treatment. Scr Mater 137:36–40
Xie ZJ, Yuan SF, Zhou WH, Yang JR, Guo H, Shang CJ (2014) Stabilization of retained austenite by the two-step intercritical heat treatment and its effect on the toughness of a low alloyed steel. Mater Des 59:193–198
Zhou WH, Wang XL, Venkatsurya PKC, Guo H, Shang CJ, Misra RDK (2014) Structure–mechanical property relationship in a high strength low carbon alloy steel processed by two-step intercritical annealing and intercritical tempering. Mater Sci Eng, A 607:569–577
Xu YB, Hu ZP, Zou Y, Tan XD, Han DT, Chen SQ et al (2017) Effect of two-step intercritical annealing on microstructure and mechanical properties of hot-rolled medium manganese TRIP steel containing δ-ferrite. Mater Sci Eng, A 688:40–55
Hu B, Luo H (2019) A novel two-step intercritical annealing process to improve mechanical properties of medium Mn steel. Acta Mater 176:250–263
Ma J, Lu Q, Sun L et al (2018) Two-step intercritical annealing to eliminate lüders band in a strong and ductile medium Mn steel. Metall Mater Trans A 49(10):4404–4408
Ding R, Dai Z, Huang M, Yang Z, Zhang C, Chen H (2018) Effect of pre-existed austenite on austenite reversion and mechanical behavior of an Fe–0.2C–8Mn–2Al medium Mn steel. Acta Mater 147:59–69
Chen J, Lv MY, Liu ZY et al (2016) Influence of heat treatments on the microstructural evolution and resultant mechanical properties in a low carbon medium mn heavy steel plate. Metall Mater Trans A 47(5):2300–2312
Seo C, Kwon KH, Choi K, Kim K, Kwak JH, Lee S et al (2012) Deformation behavior of ferrite–austenite duplex lightweight Fe–Mn–Al–C steel. Scr Mater 66:519–522
Wei R, Enomoto M, Hadian R, Zurob HS, Purdy GR (2013) Growth of austenite from as-quenched martensite during intercritical annealing in an Fe–01C–3Mn–15Si alloy. Acta Mater 61:697–707
Dmitrieva O, Ponge D, Inden G, Millán J, Choi P, Sietsma J et al (2011) Chemical gradients across phase boundaries between martensite and austenite in steel studied by atom probe tomography and simulation. Acta Mater 59:364–374
Nakada N, Mizutani K, Tsuchiyama T, Takaki S (2014) Difference in transformation behavior between ferrite and austenite formations in medium manganese steel. Acta Mater 65:251–258
Shao C, Hui W, Zhang Y, Zhao X, Weng Y (2017) Microstructure and mechanical properties of hot-rolled medium-Mn steel containing 3% aluminum. Mater Sci Eng, A 682:45–53
Sugimoto KI, Kobayashi M, Hashimoto SI (1992) Ductility and strain-induced transformation in a high-strength transformation-induced plasticity-aided dual-phase steel. Metall Trans A 23:3085–3091
Feng XH, Zhao J, Quan CW, Shi J, Yun WC, Li J et al (2012) Tempering effects on the stability of retained austenite and mechanical properties in a medium manganese steel. ISIJ Int 52:868–873
Matsumura O, Sakuma Y, Takechi H (1987) Trip and its kinetic aspects in austempered 04C–15Si–08Mn steel. Scr Metall 21:1301–1306
Cottrell AH, Bilby BA (1949) Dislocation theory of yielding and strain ageing of iron. Proc Phys Soc A 62:49
Sun B, Vanderesse N, Fazeli F, Scott C, Chen J, Bocher P et al (2017) Discontinuous strain-induced martensite transformation related to the Portevin-Le Chatelier effect in a medium manganese steel. Scr Mater 133:9–13
Li WS, Gao HY, Nakashima H, Hata S, Tian WH (2016) In-situ study of the deformation-induced rotation and transformation of retained austenite in a low-carbon steel treated by the quenching and partitioning process. Mater Sci Eng, A 649:417–425
Wang XG, Wang L, Huang MX (2017) Kinematic and thermal characteristics of Lüders and Portevin-Le Châtelier bands in a medium Mn transformation-induced plasticity steel. Acta Mater 124:17–29
Lee S, Kim J, Kane SN, Cooman BCD (2011) On the origin of dynamic strain aging in twinning-induced plasticity steels. Acta Mater 59:6809–6819
Koyama M, Sawaguchi T, Lee T, Lee CS, Tsuzaki K (2011) Work hardening associated with ɛ-martensitic transformation, deformation twinning and dynamic strain aging in Fe–17Mn–06C and Fe–17Mn–08C TWIP steels. Mater Sci Eng, A 528:7310–7316
This work was financially supported by the National Key R&D Program of China (2017YFB0304105). Professor R.D.K. Misra gratefully acknowledges continued collaboration with Northeastern University as Honorary Professor by providing guiding to studies in research.
Conflict of interest
The authors declare that they have no conflict of interest.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Han, D.T., Xu, Y.B., Peng, F. et al. The determining role of pre-annealing on Mn partitioning behavior in medium-Mn-TRIP steel: experimental and numerical simulation. J Mater Sci 55, 4437–4452 (2020) doi:10.1007/s10853-019-04256-3