تاثیر انجام تغییرشکل پلاستیک شدید به روش پیچش تحت فشار بالا بر ریزساختار، خواص مکانیکی و رفتار سودوالاستیسیته فولاد Fe-10Ni-7Mn (wt.%)آنیل‌شده در منطقه دو فازی آستنیت-فریت

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی متالورژی و مواد، دانشگاه تهران، تهران، ایران

2 دکترای دانشکده مهندسی متالورژی و مواد دانشگاه توهوکو ژاپن

3 دانشکده مهندسی متالورژی و مواد، دانشگاه علم و صنعت ایران، تهران، ایران

4 استاد دانشکده مهندسی متالورژی و مواد دانشگاه تهران

چکیده

در پژوهش حاضر، تاثیر تغییرشکل پلاستیک شدید به روش پیچش تحت فشار بالا به همراه آنیل در منطقه دو فازی فریت-آستنیت بر ریزساختار، خواص مکانیکی و سودوالاستیسیته فولاد مارتنزیتی کم کربن Fe-10Ni-7Mn (wt.%) مورد بررسی قرار گرفت. بدین منظور نمونه ها در سه حالت پس از آنیل محلولی و آنیل هم دما در دماهای ℃ 580 و 600 به مدت 2 ساعت در معرض فرآیند پیچش تحت فشار بالا قرار گرفتند. نتایج حاکی از آن است که اعمال 20 دور فرآیند پیچش تحت فشار بالا بر نمونه های آنیل محلولی و آنیل شده موجب بهبود چشمگیر سختی و استحکام نهایی، کاهش اندازه دانه به ابعاد نانومتری و دستیابی به چکش خواری مطلوب شده است. بررسی های فازی نشان داد که فرآیند پیچش تحت فشار بالا موجب رخداد دگرگونی معکوس مارتنزیت به آستنیت در نمونه آنیل محلولی و دگرگونی آستنیت به مارتنزیت در نمونه های آنیل شده در منطقه دوفازی آستنیت-فریت شده است. در مقایسه سه نمونه مورد مطالعه، نمونه آنیل شده در دمای C° 600 و سپس فرآوری شده با فرآیند پیچش تحت فشار بالا، سختی مطلوبتر با بیشترین میزان یکنواختی و همچنین استحکام نهایی و تغییرطول تا شکست بهینه ای نسبت به دو نمونه دیگر ارائه داد. به دلیل درصد آستنیت بیشتر موجود در ریزساختار این نمونه، اندازه دانه کوچک و استحکام نهایی بیشتر، امکان حرکت برگشت پذیر فصل مشترک فازهای آستنیت و مارتنزیت اپسیلن بهتر مهیا شد و در نتیجه میزان سودوالاستیک به دست آمده از این نمونه نسبت به دو حالت دیگر اندکی بیشتر بوده است.

کلیدواژه‌ها


عنوان مقاله [English]

Effect of Severe Plastic Deformation byHigh Pressure Torsion on the Microstructure, Mechanical Properties and Pseudoelastic Behavior of the Fe-10Ni-7Mn (wt.%) Steel after Intercritical Annealing treatment

نویسندگان [English]

  • Faezeh Javadzadeh Kalahroudi 1
  • Hamidreza Koohdar 1
  • Hassan Shirazi 2
  • Hamidreza Jafarian 3
  • Mahmoud Nili-Ahmadabadi 4
1 School of Metallurgy and Materials Engineering, University of Tehran, Tehran, Iran
2 PhD, School of Metallurgy and Materials Engineering, Tohoku University, Sendai, Japan
3 Assistant Professor, School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Iran
4 Professor, School of Metallurgy and Materials Engineering, University of Tehran
چکیده [English]

In this research, the effect of severe plastic deformation by high pressure torsion process on the microstructure, mechanical properties and pseudoelastic behavior of the Fe-10Ni-7Mn (wt.%) alloy after annealing at intercritical temperatures was investigated. The results revealed that applying high pressure torsion process for 20 turns on the solution annealed specimen and intercritical annealed samples at two different temperatures, 580 and 600°C for 2 hours, caused reasonable ductility with significant increase in micro-hardness, ultimate tensile strength and reduced grain size to nanometer. Phase evaluation by XRD and EBSD analysis showed that high pressure torsion process led to reverse transformation of martensite to austenite in solution annealed specimen and austenite to martensite transformation in the intercritical annealed samples. Among studied samples conducted in this research, the intercritical annealed sample at 600°C and subsequently deformed by high pressure torsion, revealed the most significant mechanical properties. Moreover, in this sample due to the higher fraction of austenite, fine grain size and high tensile strength, and easier reversible movement of the fcc/hcp interface, more amount of pseudoelasticity was achieved in comparison to the others samples.

کلیدواژه‌ها [English]

  • Fe-10Ni-7Mn (wt.%) Low carbon martensitic steel
  • High pressure torsion
  • Intercritical annealing in the dual-phase region
  • Mechanical properties
  • Psuedoelastic behavior
 
[1]     R. Decker, S. Floreen, and R. Wilson, "Maraging steels: recent developments and applications," in Proceedings of the Symposium of TMS Annual Meeting, 1988, pp. 1-38.
[2]     S. Floreen, R. Decker, and R. Decker, "Source book on maraging steels," ASM, Metals Park, OH, pp. 20-32, 1979.
[3]     س. حسین. نژاد, "فولادهای مارجینگ: از ابداع تا به امروز," مهندسی متالورژی1381.
[4]     H. R. Koohdar, M. Nili-Ahmadabadi, M. Habibi-Parsa, H. R. Jafarian, H. Ghasemi-Nanesa, and H. Shirazi, "Observation of pseudoelasticity in a cold rolled Fe–Ni–Mn martensitic steel," Materials Science and Engineering: A, vol. 658, pp. 86-90, 2016.
[5]     H. R. Koohdar, M. Nili-Ahmadabadi, M. Habibi-Parsa, and H. R. Jafarian, "Development of pseudoelasticity in Fe–10Ni–7Mn (wt%) high strength martensitic steel by intercritical heat treatment and subsequent ageing," Materials Science and Engineering: A, vol. 621, pp. 52-60, 2015.
[6]     B. Sandvik and C. Wayman, "Characteristics of lath martensite: Part I. Crystallographic and substructural features," Metallurgical transactions A, vol. 14, pp. 809-822, 1983.
[7]     D. Squires and E. Wilson, "Aging and brittleness in an Fe-Ni-Mn alloy," Metallurgical and Materials Transactions B, vol. 3, pp. 579-585, 1972.
[8]     V. Kardonskii and M. Perkas, "Aging of martensite in Fe− Ni− Mn steels," Metal Science and Heat Treatment, vol. 8, pp. 254-256, 1966.
[9]     M. Nili Ahmadabadi, H. Shirazi, H. Ghasemi-Nanesa, S. Hossein Nedjad, B. Poorganji, and T. Furuhara, "Role of severe plastic deformation on the formation of nanograins and nano-sized precipitates in Fe–Ni–Mn steel," Materials & Design, vol. 32, pp. 3526-3531, 2011.
[10]   A. Mirsepasi, M. Nili-Ahmadabadi, M. Habibi-Parsa, H. Ghasemi-Nanesa, and A. F. Dizaji, "Microstructure and mechanical behavior of martensitic steelseverely deformed by the novel technique of repetitive corrugation and straightening by rolling," Materials Science and Engineering: A, vol. 551, pp. 32-39, 2012.
[11]   H. Shirazi, M. Nili-Ahmadabadi, A. Fatehi, and S. Hossein Nedjad, "Effect of Severe Plastic Deformation on Mechanical Properties of Fe-Ni-Mn High Strength Steel," Advanced Materials Research, vol. 83-86, pp. 16-23, 2009.
[12]   H. Ghasemi-Nanesa, M. Nili-Ahmadabadi, and H. Shirazi, "Mechanical properties of Fe -10Ni -7Mn martensitic steel subjected to severe plastic deformation via cold rolling and wire drawing," Journal of Physics: Conference Series, vol. 240, p. 012117, 2010.
[13]   H. Shirazi, G. Miyamoto, S. Hossein Nedjad, H. Ghasemi-Nanesa, M. Nili Ahmadabadi, and T. Furuhara, "Microstructural evaluation of austenite reversion during intercritical annealing of Fe–Ni–Mn martensitic steel," Journal of Alloys and Compounds, vol. 577, pp. S572-S577, 2013.
[14]   H. Koohdar, M. Nili-Ahmadabadi, M. Habibi-Parsa, H. R. Jafarian, T. Bhattacharjee,and N. Tsuji, "On the Stability of Reversely Formed Austenite and Related Mechanism of Transformation in an Fe-Ni-Mn Martensitic Steel Aided by Electron Backscattering Diffraction and Atom Probe Tomography," Metallurgical and Materials Transactions A, vol. 48, pp. 5244-5257, 2017.
[15]   H. Koohdar, M. Nili-Ahmadabadi, M. Habibi-Parsa, and H. Ghasemi-Nanesa, "Investigating on the Reverse Transformation of Martensite to Austenite and Pseudoelastic Behavior in Ultrafine-Grained Fe-10Ni-7Mn (wt %) Steel Processed by Heavy Cold Rolling," Advanced Materials Research, vol. 829, pp. 25-29, 2013.
[16]   ح. کوهدار, " نانوساختارFe-Ni-Mn بهینه سازی خواص حافظه داری و سودوالاستیسیته آلیاژهای پایه
" رساله دکتری, تهران دانشگاه, 1394.
[17]   H. Ghasemi-Nanesa, M. Nili-Ahmadabadi, H. R. Koohdar, M. Habibi-Parsa, S. Hossein Nedjad, S. A. Alidokht, et al., "Strain-induced martensite to austenite reverse transformation in an ultrafine-grained Fe–Ni–Mn martensitic steel," Philosophical Magazine, vol. 94, pp. 1493-1507, 2014.
[18]   R. Pippan, "High pressure torsion: features and applications," Bulk Nanostructured Materials, pp. 217-232, 2009.
[19]   A. P. Zhilyaev, G. V. Nurislamova, B. K. Kim, M. D. Baró, J. A. Szpunar, and T. G. Langdon, "Experimental parameters influencing grain refinement and microstructural evolution during high-pressure torsion," Acta Materialia, vol. 51, pp. 753-765, 2003.
[20]   M. El-Tahawy, J. Gubicza, Y. Huang, H. L. Choi, H. M. Choe, J. L. Lábár, et al., "Evolution of Microstructure, Phase Composition and Hardness in 316L Stainless Steel Processed by High-Pressure Torsion," Materials Science Forum, vol. 879, pp. 502-507, 2016.
[21]   S. Shi, Z. Zhang, X. Wang, G. Zhou, G. Xie, D. Wang, et al., "Microstructure evolution and enhanced mechanical properties in SUS316LN steel processed by high pressure torsion at room temperature," Materials Science and Engineering: A, vol. 711, pp. 476-483, 2018.
[22]   Y. Todaka, Y. Miki, M. Umemoto, C. H. Wang, and K. Tsuchiya, "Tensile Property of Submicrocrystalline Pure Fe Produced by HPT-Straining," Materials Science Forum, vol. 584-586, pp. 597-602, 2008.
[23]   J. Gubicza, M. El-Tahawy, Y. Huang, H. Choi, H. Choe, J. L. Lábár, et al., "Microstructure, phase composition and hardness evolution in 316L stainless steel processed by high-pressure torsion," Materials Science and Engineering: A, vol. 657, pp. 215-223, 2016.
[24]   Y. Ivanisenko, I. Maclaren, X. Sauvage, R. Valiev, and H. Fecht, "Shear-induced α→γ transformation in nanoscale Fe–C composite," Acta Materialia, vol. 54, pp. 1659-1669, 2006.
[25]   R. B. Figueiredo, F. L. Sicupira, L. R. C. Malheiros, M. Kawasaki, D. B. Santos, and T. G. Langdon, "Formation of epsilon martensite by high-pressure torsion in a TRIP steel," Materials Science and Engineering: A, vol. 625, pp. 114-118, 2015.
[26]   H. Ghasemi-Nanesa, M. Nili-Ahmadabadi, H. Shirazi, S. Hossein Nedjad, and S. H. Pishbin, "Ductility enhancement in ultrafine-grained Fe–Ni–Mn martensitic steel by stress-induced reverse transformation," Materials Science and Engineering: A, vol. 527, pp. 7552-7556, 2010.
[27]   J. G. Li, M. Umemoto, Y. Todaka, and K. Tsuchiya, "Formation of Ultrafine Grained Structure in SUS 304 Stainless Steel Produced by High Pressure Torsion (HPT)," Materials Science Forum, vol. 561-565, pp. 847-852, 2007.
[28]   H. Ghasemi-Nanesa, M. Nili Ahmadabadi, H. Shirazi, and S. Hossein Nedjad, "Observation of Reverse Transformation of α-ε-γ in ultrafine - grained Fe-Ni-Mn Age Hardenable Martensitic Steel," International Journal of Modern Physics: Conference Series, vol. 05, pp. 9-17, 2012.
[29]   R. Z. Valiev and A. A. Nazarov, "Bulk Nanostructured Materials by SPD Processing: Techniques, Microstructures and Properties," in Bulk Nanostructured Materials, M. J. Zehetbauer and Y. T. Zhu, Eds., ed: WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, 2009, pp. 21-48.
[30]   T. Sawaguchi, T. Kikuchi, and S. Kajiwara, "The pseudoelastic behavior of Fe–Mn–Si-based shape memory alloys containing Nb and C," Smart Materials and Structures, vol. 14, pp. S317-S322, 2005.
[31]   پ. حکیمی. پور, "تأثیر انجام عملیات تغییر شکل پلاستیک بر رفتار سودو الاستیک فولاد مارتنزیتی فوق ریزدانهFe-10Ni-7Mn (%wt)," رساله کارشناسی ارشد, دانشگاه تهران, 1394.