<p>This study presents a mathematical model to understand the effect of process parameters on the resulting temperature distribution in a steel disk during its differential heating. The model is based on the numerical solution of the heat conduction equation under appropriate initial and boundary conditions, and it was validated by comparing the temperature results with previously reported laboratory measurements. Disks of Usibor and 22MnB5 steel grades, were partially covered using isolating shields and heated in an electric resistance muffle at temperatures of 900 and 1000&#xa0;°C. Numerical analysis showed the role of shield thickness and thermal properties on the resulting temperature field in the steel disk. This temperature gradient is of prime importance to obtain differential microstructures after heating and the corresponding differential microstructure and properties in the quenched sheet.</p> Graphical abstract <p></p>