Application of 3D finite element method (FEM) simulation for induction hardening of gears is still a time-consuming and expensive task. The significant cost of a simulation remains in the manual preparation of the 3D description of geometry. In the current work, we propose to complement the numeric simulations with automatic geometry generation based on a parametric representation of a gear and an induction coil. The parameters used to describe a gear are module, pitch diameter, and pressure angle. The circular coil is described by the height, external and internal diameters. FEM computations are implemented to solve magneto-quasi-static Maxwell’s equations. A demonstration of the possibilities of the proposed approach via a parametric study is presented by varying the module of a gear while keeping a constant number of teeth. A heuristic tuning of heating power frequency- time is presented here and compared to the classical semi-analytical equations and 2D simulations.

The development of residual stress in an induction hardened small spur gear is numerically simulated. A full scale 3D simulation is utilized to obtain the results, providing the possibility to evaluate the complete distribution of residual stress in the hardened component. Electromagnetic and thermal solutions under induction heating conditions are obtained with Cedrat Flux 3D, whereas EDF Code Aster software is used for thermal simulation during the quenching stage, phase transformation, and stress-strain simulations. The simulated induction heating isotherms and distribution of residual stress are compared with experimental investigations done by Larregain et al. and Savaria et al.

The possibility to manage stress and strain in hardened parts might be beneficial for a number of induction hardening applications. The most important of these benefits is the improvement of fatigue strength, avoidance of cracks and minimization of distortion. An appropriate and powerful way to take the stress and strain into account during the development of a process is to make use of computer simulations. Own developed and commercial software packages have been coupled to incorporate the electromagnetic task into the calculations. The simulations have been performed with a following analysis of the results. The influences of two different values of quenching intensity, strength of initial material structure, strength of austenite, surface power density-frequency-time-combination, and work piece diameter on the residual stress are studied.