Research on dynamic hardening effect on workpiece's hardness distribution with depth of cut

摘要

Grinding hardening is a kind of attractive processing technology, which utilizes grinding heat to generate the hardening layers. Previous studies have attached the importance on generation mechanism in experiments and simulations. However, grinding hardening is a dynamic hardness improvement process due to the system's dynamic characteristics, whose hardness becomes different during the dynamic process. To this end, this paper presents a new hybrid model to investigate the dynamic hardness distribution with the system's dynamic characteristics. When the effect of cutting, rubbing, and plowing is considered, the dynamic grinding force is calculated firstly. Afterwards, coupled with the dynamic grinding force, the dynamic grinding temperature distribution is obtained accordingly. Moreover, in terms of the hardness superposition rule, the dynamic hardness model is established based on the calculated dynamic grinding force and the dynamic temperature distribution. Finally, the model is validated by the measurement of the ground workpiece's hardness via grinding experiments under different grinding depths. It can be concluded that the system's dynamic characteristics can result in the time delay of the hardness temporal distribution and the inhomogeneity of the hardness spatial distribution. Consequently, the model is anticipated to be meaningful for both the manufacturing industries and the research fields.