Samuel, A.Pranesh Rao, K.M.Prabhu, K.N.2026-02-032025Journal of Materials Engineering and Performance, 2025, 34, 6, pp. 5327-533810599495https://doi.org/10.1007/s11665-024-09448-whttps://idr.nitk.ac.in/handle/123456789/20405The depth of hardness in during quench hardening of steels depends on the steel composition, section thickness, and the boundary heat transfer coefficient. A simulation study is performed in the present work to optimize the heat transfer coefficients for selecting quenchants for a particular grade of steel and section thickness. The simulation study is performed by solving phase transformation coupled transient heat conduction equation using the finite element method. The finite element model adopted in this work uses the one-dimensional radially symmetric model with a constant heat transfer coefficient boundary condition at the surface. The variables in the simulation study are the carbon content, the diameter of steel, and the heat transfer coefficients. The effect of these variables on the martensite formation is studied. A critical heat transfer coefficient is defined corresponding to a 50 pct. martensite transformation at the core of the steel cylindrical specimens. The critical heat transfer coefficient increased with the increase in the diameter; whereas, it showed a parabolic relation with the carbon content. The usefulness of the study in selecting a suitable quenchant for quench hardening of plain carbon steels with varying carbon content is illustrated. © ASM International 2024.Finite element methodHardeningHeat transfer coefficientsMartensiteCarbon contentCritical heat transferHardenabilityHeat transfer co-efficientsQuench hardeningQuenchant selectionQuenchantsSection thicknessSimulation studiesSteel compositionsHeat conduction