Understanding the hot-deformation response of microalloyed wheel steels is essential for selecting rolling conditions that balance strength, ductility, and processability. This study examines the influence of deformation temperature, strain rate, and deformation degree on the flow stress of low-pearlite microalloyed 10HFTBch steel tested on a Gleeble 3800 simulator. After a controlled pre-treatment of 7 mm blanks, the experimentally observed rheological trends were interpreted within a Hansel–Spittel constitutive framework. To improve mathematical transparency, the manuscript distinguishes clearly between the generic Hansel–Spittel formulation, its reduced hot-deformation form, and the calibrated analytical approximation used to construct the response surfaces. Within the analyzed process window, increasing temperature reduced flow stress, whereas increasing strain and strain rate increased deformation resistance. The strongest global agreement between experimental observations and the analytical surfaces was obtained for the temperature–strain representation (r = 0.978), while the temperature–strain-rate and strain–strain-rate surfaces also showed strong correlations (r = 0.962 and r = 0.963, respectively). These adequacy indicators are interpreted conservatively as measures of overall agreement rather than as a substitute for full residual-based validation. When integrated with earlier thermokinetic and hot-rolling studies on the same steel grade, the present analysis supports a practical processing window centered on finishing rolling near 850 °C, initiating accelerated cooling near 750 °C, and coiling near 600 °C. Under those conditions, previously reported strength, ductility, and impact-toughness levels indicate that 10HFTBch steel is a promising candidate for heavily loaded wheel applications.