Research on the Size Distribution of Intragranular and Boundary Carbides of T91 Steel after Creep

Abstract:

The high temperature crept tests of T91 steel have been conducted under two different stresses and temperatures. The single crystal electron diffraction is used to identify the precipitated phase structure. The quantity and size of carbides located in boundaries and intragranular area have been obtained by quantitative metallography, respectively. The results showed that the main precipitated carbides in T91 steel are M₂₃C₆(M=Fe,Cr) and V₄C_3, which is located in the grain and at the boundary of prior austenite respectively. In comparison with the carbides at boundary, the average size of intragranular carbides was smaller while the quantity is higher. The distribution of the carbides size crept with different stresses and temperatures is in accordance with a typical Boltzmann distribution.

• Periodical: Advanced Materials Research (Volumes 941-944)
• Pages: 198-205
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.941-944.198
• Online since: June 2014
• Authors: Qiang Wan, L. Chen, C. Luo, Z.G. Li, Y.M Chen, B. Yang*
• Keywords: Carbides Size, Distribution Function, Quantity, T91 Steel

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