Impact of L1₂-Ordered Precipitation on the Strength of Alumina-Forming Austenitic Heat-Resistant Steels

Abstract:

Alumina-forming austenitic (AFA) heat-resistance steels firstly developed by Yamamoto et al. at Oak Ridge National Laboratory have been reported as a new promising class of steels with potential for use in high temperature applications in recent years. The creep resistance of AFA steels is improved mainly by precipitation strengthening. Besides modifying the typical existing precipitates, i.e. MC and M₂₃C₆ type carbides, B2-NiAl and Fe₂Nb-type Laves phase, introduction of coherent L1₂-ordered precipitate is highly desired. L1₂-ordered phase gamma prime (γ’) is the most important precipitate for high-temperature strengthening in Ni-based superalloys. In the present work, we demonstrate that addition of 2.8 wt. % Cu to an AFA steel promotes the formation of an L1₂-ordered phase with the dominating elements Ni, Cu and Al. TEM characterization after slow rate tensile tests indicated there were the different precipitation behaviours at 700°C and 750°C. It was revealed that the occurrence of L1₂-ordered Ni-Cu-Al phase depends on temperature and Ni content. This opens up new opportunities to promote the formation of L1₂-ordered phase in Fe-based austenitic heat-resistance steels and benefit high-temperature mechanical properties.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 692-697
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.692
• Online since: December 2018
• Authors: Bing Bing Zhao*, Xian Ping Dong, Feng Sun, Lan Ting Zhang
• Keywords: Alumina-Forming Austenitic Steel, L1₂-Ordered Precipitates, MC Carbides, Slow Rate Tensile Test

References

[1] A. Aghajani, C. Somsen, G. Eggeler, On the effect of long-term creep on the microstructure of a 12% chromium tempered martensite ferritic steel, Acta Materialia, 57 (2009) 5093-5106.

DOI: 10.1016/j.actamat.2009.07.010

[2] L. Cipolla, H.K. Danielsen, D. Venditti, P.E. Di Nunzio, J. Hald, M.A.J. Somers, Conversion of MX nitrides to Z-phase in a martensitic 12% Cr steel, Acta Materialia, 58 (2010) 669-679.

DOI: 10.1016/j.actamat.2009.09.045

[3] F. Abe, Strengthening Mechanisms in Creep of Advanced Ferritic Power Plant Steels Based on Creep Deformation Analysis, in: Y. Weng, H. Dong, Y. Gan (Eds.) Advanced Steels, Springer Berlin Heidelberg, 2011, pp.409-422.

DOI: 10.1007/978-3-642-17665-4_42

[4] V. Viswanathan, R. Purgert, P. Rawls, Coal-fired power materials, Advanced Materials and Processes, 8 (2008) 47-49.

[5] Y. Yamamoto, M.P. Brady, M.L. Santella, H. Bei, P.J. Maziasz, B.A. Pint, Overview of Strategies for High-Temperature Creep and Oxidation Resistance of Alumina-Forming Austenitic Stainless Steels, Metall and Mat Trans A, 42 (2011) 922-931.

DOI: 10.1007/s11661-010-0295-2

[6] Y. Yamamoto, M.P. Brady, Z.P. Lu, P.J. Maziasz, C.T. Liu, B.A. Pint, K.L. More, H.M. Meyer, E.A. Payzant, Creep-Resistant, Al2O3-Forming Austenitic Stainless Steels, Science, 316 (2007) 433-436.

DOI: 10.1126/science.1137711

[7] Y. Yamamoto, M. Takeyama, Z.P. Lu, C.T. Liu, N.D. Evans, P.J. Maziasz, M.P. Brady, Alloying effects on creep and oxidation resistance of austenitic stainless steel alloys employing intermetallic precipitates, Intermetallics, 16 (2008) 453-462.

DOI: 10.1016/j.intermet.2007.12.005

[8] X. Xu, X. Zhang, X. Sun, Z.P. Lu, Effects of silicon additions on the oxide scale formation of an alumina-forming austenitic alloy, Corrosion Science, 65 (2012) 317-321.

DOI: 10.1016/j.corsci.2012.08.039

[9] D.Q. Zhou, X.Q. Xu, H.H. Mao, Y.F. Yan, T.G. Nieh, Z.P. Lu, Plastic flow behaviour in an alumina-forming austenitic stainless steel at elevated temperatures, Materials Science and Engineering: A, 594 (2014) 246-252.

DOI: 10.1016/j.msea.2013.11.021

[10] M. Wang, H. Sun, M.P. Phaniraj, H.N. Han, J. Jang, Z. Zhou, Evolution of microstructure and tensile properties of Fe–18Ni–12Cr based AFA steel during aging at 700 °C, Materials Science and Engineering: A, 672 (2016) 23-31.

DOI: 10.1016/j.msea.2016.06.060

[11] J. Moon, T.-H. Lee, Y.-U. Heo, Y.-S. Han, J.-Y. Kang, H.-Y. Ha, D.-W. Suh, Precipitation sequence and its effect on age hardening of alumina-forming austenitic stainless steel, Materials Science and Engineering: A, 645 (2015) 72-81.

DOI: 10.1016/j.msea.2015.08.005

[12] G. Trotter, B. Hu, A.Y. Sun, R. Harder, M.K. Miller, L. Yao, I. Baker, Precipitation kinetics during aging of an alumina-forming austenitic stainless steel, Materials Science and Engineering: A, 667 (2016) 147-155.

DOI: 10.1016/j.msea.2016.04.081

[13] M.P. Brady, J. Magee, Y. Yamamoto, D. Helmick, L. Wang, Co-optimization of wrought alumina-forming austenitic stainless steel composition ranges for high-temperature creep and oxidation/corrosion resistance, Materials Science and Engineering: A, 590 (2014) 101-115.

DOI: 10.1016/j.msea.2013.10.014

[14] J. Moon, M.-H. Jang, J.-Y. Kang, T.-H. Lee, The negative effect of Zr addition on the high temperature strength in alumina-forming austenitic stainless steels, Materials Characterization, 87 (2014) 12-18.

DOI: 10.1016/j.matchar.2013.10.029

[15] M.-H. Jang, J. Moon, J.-Y. Kang, H.-Y. Ha, B.G. Choi, T.-H. Lee, C. Lee, Effect of tungsten addition on high-temperature properties and microstructure of alumina-forming austenitic heat-resistant steels, Materials Science and Engineering: A, 647 (2015) 163-169.

DOI: 10.1016/j.msea.2015.09.018

[16] K.A. Terrani, C.M. Parish, D. Shin, B.A. Pint, Protection of zirconium by alumina- and chromia-forming iron alloys under high-temperature steam exposure, Journal of Nuclear Materials, 438 (2013) 64-71.

DOI: 10.1016/j.jnucmat.2013.03.006

[17] M.-H. Jang, J.-Y. Kang, J.H. Jang, T.-H. Lee, C. Lee, The role of phosphorus in precipitation behavior and its effect on the creep properties of alumina-forming austenitic heat-resistant steels, Materials Science and Engineering: A, 684 (2017) 14-21.

DOI: 10.1016/j.msea.2016.12.021

[18] Y. Yamamoto, G. Muralidharan, M.P. Brady, Development of L1(2)-ordered Ni-3(Al,Ti)-strengthened alumina-forming austenitic stainless steel alloys, Scripta Materialia, 69 (2013) 816-819.

DOI: 10.1016/j.scriptamat.2013.09.005

[19] B. Zhao, J. Fan, Y. Liu, L. Zhao, X. Dong, F. Sun, L. Zhang, Formation of L12-ordered precipitation in an alumina-forming austenitic stainless steel via Cu addition and its contribution to creep/rupture resistance, Scripta Materialia, 109 (2015) 64-67.

DOI: 10.1016/j.scriptamat.2015.07.019

[20] B. Zhao, K. Chang, J. Fan, Z. Chen, X. Dong, L. Zhang, Annealing effects on precipitation and high-temperature properties of a Cu-containing alumina-forming austenitic steel, Materials Letters, 176 (2016) 83-86.

DOI: 10.1016/j.matlet.2016.04.110

[21] B. Zhao, J. Fan, Z. Chen, X. Dong, F. Sun, L. Zhang, Evolution of precipitates in a Cu-containing alumina-forming austenitic steel after short-term mechanical tests, Materials Characterization, 125 (2017) 37-45.

DOI: 10.1016/j.matchar.2017.01.023

[22] B. Hu, G. Trotter, Z. Wang, S. Chen, Z. Cai, I. Baker, Effect of boron and carbon addition on microstructure and mechanical properties of the aged gamma-prime strengthened alumina-forming austenitic alloys, Intermetallics, 90 (2017) 36-49.

DOI: 10.1016/j.intermet.2017.06.011

[23] D. Baither, T. Krol, E. Nembach, In-situ transmission electron microscopy study of dislocation processes at precipitate-free zones in a γ '-strengthened superalloy, Philos. Mag., 83 (2003) 4011-4029.

DOI: 10.1080/14786430310001603445