Numerical analysis of 3D spot continual induction hardening on curved surface of AISI 1045 steel

In order to investigate and predict the material properties of curved surface AISI 1045 steel component during spot continual induction hardening (SCIH), a 3D model for curved surface workpieces which coupled electromagnetic, temperature and phase transformation fields was built by finite element software ANSYS. A small size inductor and magnetizer were used in this model, which can move along the top surface of workpiece flexibly. The effect of inductor moving velocity and workpiece radius on temperature field was analyzed and the heating delay phenomenon was found through comparing the simulated results. The temperature field results indicate that the heating delay phenomenon is more obvious under high inductor moving velocity condition. This trend becomes more obvious if the workpiece radius becomes larger. The predictions of microstructure and micro-hardness distribution were also carried out via this model. The predicted results show that the inductor moving velocity is the dominated factor for the distribution of 100% martensite region and phase transformation region. The influencing factor of workpiece radius on 100% martensite region and phase transformation region distribution is obvious under relatively high inductor moving velocity but inconspicuous under relatively low inductor moving velocity.