Abstract
The deformation behavior and the microstructure evolution under the creep of 10Kh9V2MFBR steel (Russian analog of the P92 steel) (in wt %, Fe–8.9% Cr–0.05% Si–0.2% Mn–1.9% W–0.5% Mo–0.25% V–0.07Nb–0.08% N–0.01% B) with the standard (0.1%) and lowered (0.018%) carbon contents have been investigated. After the heat treatment, which included normalizing at 1050°C and tempering at 720–750°C, carbides M 23 C 6 and carbonitrides M(C,N) are formed in the 10Kh9V2MFBR steel, while in the 02Kh9V2MFBR steel (modified P92 steel), carbides M 23 C 6, nitrides M 2N, and carbonitrides M(C,N) as well as δ-ferrite (23%) were found. The measurements of hardness and tensile tests at room and elevated temper-atures did not reveal substantial distinctions in the short-term mechanical properties of both steels. The hardness of steels after tempering was 220 HB. At the same time, the creep characteristics of the steels were found to be different. A decrease in the carbon content leads to an increase in the long-term creep strength and creep limit at 650°C for short-term tests with time-to-fracture shorter than 103 h. The time to fracture of steels with various carbon contents is almost the same in long-term creep tests. Factor responsible for such effect of carbon on the creep strength are discussed.
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Original Russian Text © V.A. Dudko, A.E. Fedoseeva, A.N. Belyakov, R.O. Kaibyshev, 2015, published in Fizika Metallov i Metallovedenie, 2015, Vol. 116, No. 11, pp. 1222–1232.
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Dudko, V.A., Fedoseeva, A.E., Belyakov, A.N. et al. Influence of the carbon content on the phase composition and mechanical properties of P92-type steel. Phys. Metals Metallogr. 116, 1165–1174 (2015). https://doi.org/10.1134/S0031918X15110058
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DOI: https://doi.org/10.1134/S0031918X15110058