Evolution of Laves-Phase Particles in a Low Carbon 9%Cr Martensitic Steel during Creep at 650°C

Abstract:

The evolution of microstructure in low carbon heat resistant steel of P92-type modified with 3%Co was examined during creep tests at 923K for 500, 1500, 6000 and 16000 hours. After tempering at 1023K (750°C), the steel was composed of martensite lath structure with numerous precipitates of MX-type carbonitrides and rare M₂₃C₆-type carbides. The structural changes during creep tests are characterized by an increase in the sizes of laths and second phase particles. Moreover, the Fe₂W Laves-phase precipitates during long-term creep. The Laves-phase particles grow accordingly to power-law relationship of creep time.

• Periodical: Advanced Materials Research (Volume 922)
• Pages: 155-160
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.922.155
• Online since: May 2014
• Authors: Irina Fedorova*, Andrey Belyakov, Pavel Kozlov, Vladimir Skorobogatykh, Izabella Schenkova, Rustam Kaibyshev
• Keywords: Creep Resistance, Creep Resistant Steel, Laves-Phase Particles, Tempered Lath Martensite

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