Microwave thermal stress method cutting Al₂O₃ ceramics: modeling and experiments

In this study, a developed two-dimensional microwave-cutting Al₂O₃ ceramics model along with the thermodynamic and thermal stress is presented, considering the thermal conduction, convection, and radiation effects. The extended finite element method (XFEM) is innovatively proposed to evaluate the temperature field and stress field distribution. The temperature and stress distributions under different time, power, and scanning velocity are obtained by simulation. The results indicate that there is a positive correlation between temperature and microwave power. Nevertheless, the temperature registers a negative relationship with the scanning velocity. As for the higher velocity, the highest temperatures of microwave-cutting Al₂O₃ ceramics are nearly the same, and the higher velocity is not an indispensable factor in the temperature profiles of microwave-cutting ceramics. Notably, compressive stress is the primary interaction that induces crack propagation. At the front of the crack is the compressive stress and the location where the crack grows is the tensile stress. The location of the compressive stress is the direction of its crack propagation and the tensile stress causes it to crack. Finally, the study would not only provide a theoretical reference, but also pave the way for the national defense, aerospace, and semiconductor industries in the near future.