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@article{194777,
        author = {G RETHISH and Prof. N. Thennammai and Dr. K. Venkatesan},
        title = {INVESTIGATION ON SUBMERGED ARC WELDED 9%Cr 1%Mo (GRADE 91) STEEL},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {10},
        pages = {5193-5197},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=194777},
        abstract = {The present study investigates the mechanical, metallurgical, and microstructural characteristics of Submerged Arc Welded (SAW) 9Cr–1Mo (Grade 91/P91) steel, widely used in high-temperature and high-pressure applications such as power plants. Welding of P91 steel poses significant challenges due to its high hardenability and susceptibility to heat-affected zone (HAZ) degradation and cracking. In this work, SAW was performed on 20 mm thick P91 plates using Thermanit MTS-3 filler wire under controlled thermal conditions. The welded specimens were evaluated through chemical, mechanical, and microstructural analyses. Mechanical characterization included tensile, impact, hardness, and elevated temperature tensile testing. Microstructural evaluation was conducted using optical microscopy and SEM. The results revealed uniform hardness distribution without excessive hard zones, satisfactory tensile properties with fracture occurring in the base metal, and good high-temperature performance. However, impact toughness showed significant variation, particularly low values in the weld metal region. The study concludes that while SAW welded P91 joints exhibit adequate strength and high-temperature performance, optimization of post-weld heat treatment is necessary to improve toughness and ensure reliability in critical applications.},
        keywords = {P91 steel, Submerged Arc Welding, Heat Affected Zone, Mechanical Properties, Microstructure, High-temperature performance},
        month = {March},
        }