Precipitate Phases in Normalized Ferritic/Martensitic Steel P92

Abstract:

Precipitate phases in the P92 F/M steel after normalization at 1323 K (1050 °C) for 30 min followed by air cooling to room temperature have been investigated by transmission electron microscopy (TEM). Three types of phases consisting of M₃C, MX and M₂C have been identified. Needle-like Fe-rich M₃C carbide, (Fe_0.87Cr_0.13)₃C, has a simple orthorhombic lattice, and a size of 7-18 nm in short axis and 73-190 nm in long axis. Sphere-shaped Nb-rich MC carbide with a f.c.c. crystal structure has a chemical formula of about (Nb_0.69V_0.15Fe_0.1Mo_0.06)C and a size of 12 to 88 nm in diameter. Large-sized Fe-rich M₂C phase exhibits a block-like shape, and has a hexagonal crystal structure. TEM examination indicated that the number density of both the Fe-rich M₃C carbide and Nb-rich MX phase is higher than Fe-rich M₂C carbide phase.

• Periodical: Key Engineering Materials (Volume 777)
• Pages: 356-360
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.777.356
• Online since: August 2018
• Authors: Zhi Qiang Xu, Yin Zhong Shen*, Peng Cheng Zhu, Wen Wen Liu
• Keywords: Normalization, P92 Steel, Precipitate Phases, Transmission Electron Microscopy

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