Effect of the precipitation hardening on regularities of plastic deformation and fracture mode of V-alloyed high nitrogen austenitic steel
Keywords:high nitrogen steel, Fe-19Cr-22Mn-1,5V-0,3C-0,86N, austenite, precipitation hardening, σ-phase, carbonitrides, discontinuous decomposition
Nitrogen alloying of austenitic steels increases their corrosion resistance and improves mechanical properties. During heat treatment, high-nitrogen austenitic steels tend to the precipitation hardening and the increase of strength characteristics. In the current paper, the authors studied the effect of the duration of age-hardening at the temperatures of 700 °С and 800 °С on the structure, phase composition, plastic flow behavior, and fracture mechanisms of V-alloyed high nitrogen chrome-manganese austenitic Fe-19Cr-22Mn-1.5V-0.3C-0.86N (mass %) steel. The study revealed that after water-quenching at 1200 °С, the specimens possess the high strength properties, ductility and contain large (300–500 nm) (V,Cr)(N,C) particles. Aging at temperatures of 700 °С and 800 °С facilitates complex reactions of austenite discontinuous decomposition with the Cr2N-plate formation in grains and continuous decomposition with the formation of vanadium nitride-based particles in austenite. During the long-term aging (50 h at 700 °C and 10 h at 800 °C), the intermetallic σ-phase appears in specimens. At age-hardening, the observed phase transformations cause the changes in macro- and micro-mechanism of fracture in the specimens of steel under the study. In the initial state, the specimens show mainly the ductile transgranular fracture. After age-hardening, the fracture mechanism changes into the mixed mechanism with the elements of brittle intergranular and ductile transgranular fractures. When increasing the duration of aging and implementation of complex reactions of decomposition of solid solution, the specimens are fractured by the quasi-cleavage mechanism. The specimens aged at temperatures of 700 °С and 800 °С have quite similar precipitation hardening mechanisms, though the increase in aging temperature leads to the rising of the decomposition rate of solid solution. The sequence of transformations described above and the corresponding sequence of changes in the mechanisms of steel fracture are implemented faster when increasing the aging temperature.
Yuan Z., Dai Q.X., Cheng X.N., Chen K.M. Microstructural thermostability of high nitrogen austenitic stainless steel. Materials Characterization, 2007, vol. 58, no. 1, pp. 87–91.
Zakharova E.G., Kireeva I.V., Chumlyakov Yu.I., Maier H. The effect of aluminium on strain-hardening mechanisms of austenitic Hadfield steel single crystals. Fizicheskaya mezomekhanika, 2004, vol. 7, no. S1-1, pp. 233–236.
Simmons J.W. Overview: High-nitrogen alloying of stainless steels. Materials Science and Engineering A, 1996, vol. 207, no. 2, pp. 159–169.
Sagaradze V.V., Uvarov A.I. Uprochnenie i svoystva austenitnykh staley [Hardening and properties of austenitic steels]. Ekaterinburg, RIO UrO RAN Publ., 2013. 720 p.
Sagaradze V.V., Fomina O.V., Vikhareva T.V., Kataeva N.V., Kabanova I.G., Zavalishin V.A. Features of the Decomposition of Delta Ferrite in Nitrogen-Containing Austenitic Steels. Physics of Metals and Metallography, 2018, vol. 119, no. 3, pp. 296–302.
Lo K., Shek C., Lai J. Recent developments in stainless steels. Materials Science and Engineering R: Reports, 2009, vol. 65, no. 4-6, pp. 39–104.
Machado I., Carvalho P., Padilha A. Austenite instability and precipitation behavior of high nitrogen stainless steel. Stainless Steel: Microstructure, Mechanical Properties and Methods of Application. Nova Science Publishers, 2015. P. 1–36.
Qin F., Li Y., He W., Zhao X., Chen H. Aging precipitation behavior and its influence on mechanical properties of Mn18Cr18N austenitic stainless steel. Metals and Materials International, 2017, vol. 23, no. 6, pp. 1087–1096.
Babakr M., Al-Ahmari A., Al-Jumayiah K., Habiby F. Sigma phase formation and embrittlement of cast iron-chromium nickel (Fe-Cr-Ni) alloys. Journal of minerals and materials characterization and engineering, 2008, vol. 7, no. 2, pp. 127–145. DOI: 10.4236/jmmce.2008.72011.
Jiang Z., Zhang Z., Li H., Li Z., Ma Q. Evolution and mechanical properties of aging high nitrogen austenitic stainless steels. International journal of minerals, metallurgy and materials, 2010, vol. 17, no. 6, pp. 729–736.
Padilha F., Plaut L., Rios R. Annealing of cold-worked austenitic stainless steels. ISIJ International, 2003, vol. 43, no. 2, pp. 135–143.
Qiao Y., Chen J., Zhou H., Wang Y., Song Q., Li H., Zheng Z. Effect of solution treatment on cavitation erosion behavior of high-nitrogen austenitic stainless steel. Wear, 2019, vol. 424–425, pp. 70–77.
Zhang Z., Jiang Z., Li H., Zhang B., Fan S., Li Z., Feng H., Zhu H. Precipitation behavior and phase transformation mechanism of super austenitic stainless steel S32654 during isothermal aging. Materials characterization, 2018, vol. 137, pp. 244–255.
Kartik B., Veerababu R., Sundararaman M., Satyanarayana D.V.V. Effect of high temperature ageing on microstructure and mechanical properties of a nickel-free high nitrogen austenitic stainless steel. Material science and Engineering A, 2015, vol. 642, pp. 288–296.
Pettersson N., Frisk K., Fluch R. Experimental and computational study of nitride precipitation in a CrMnN austenitic stainless steel. Material science and engineering A, 2017, vol. 684, pp. 435–441.
Blinov V.M. Progress in the study of high-nitrogen corrosion-resistant aging nonmagnetic vanadium steels. Russian metallurgy, 2007, vol. 2007, no. 2, pp. 127–135.
Bannykh O., Blinov V. On the effect of discontinuous decomposition on the structure and properties of high-nitrogen steel and on methods for suppression thereof. Steel research, 1991, vol. 62, no. 1, pp. 38–45.
Knutsen R., Lang C., Basson J. Discontinuous cellular precipitation in a Cr–Mn–N steel with niobium and vanadium additions. Acta materialia, 2004, vol. 52, no. 8, pp. 2407–2417.
Jiang Z.-H., Zhang Z.-R., Li H.-B., Li Z., Ma Q.-F. Microstructural evolution and mechanical properties of aging high nitrogen austenitic stainless steels. International journal of minerals, metallurgy and materials, 2010, vol. 17, no. 6, pp. 729–736.
Naidu S., Singh T. X-ray characterization of eroded 316 stainless steel. Wear, 1993, vol. 166, no. 2, pp. 141–145.
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