Influence of Molybdenum Replacement by Tungsten in Cr Mo V Steel

Abstract:

This article aims at investigation the effect of partial and total replacement of molybdenum by tungsten in ordinary heat resistance steel, in term of constituent phases. Three steel grades of P91 steel were produced in induction furnace with different molybdenum and tungsten contents. The produced steel were hot forged at 950 °C – 1100 °C, followed by air cooling. The ordinary heat treatment was applied through austenizing at 1050 °C for one hour followed by water quenching and then, they were tempered at 700 °C for 2 hours. Optical microscope, Scanning Electron Microscope (SEM), and EDX were used to investigate the microstructure and precipitated phases after complete heat treatment process. In addition, Thermo-Calc program was used to predict the phases which may be formed. The results showed that replacement of molybdenum by tungsten has an effect on the solubility of different intermetallic phases at high temperature, delaying the deteriorative Z-phase.

• Periodical: Key Engineering Materials (Volume 835)
• Pages: 50-57
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.835.50
• Online since: March 2020
• Authors: Saeed Ghali*, Mohamed Kamal El-Fawkhry, Taha Mattar
• Keywords: Boiler Steel, Cr Steel, Mo Steel Replacing Mo by W

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