A double-ridged waveguide for low-power microwave thermal fracture cutting of low-loss glass and ceramic materials

Abstract

This paper proposes an innovative microwave technology-based approach for the precision cutting of low-loss materials, such as glass and alumina ceramics. A novel double-ridged waveguide is designed to optimize energy coupling and generate localized strong electric fields, thereby enhancing cutting efficiency. A multiphysics simulation model for microwave heating is established, incorporating a transformation optics algorithm to simulate the continuous movement of the waveguide’s sliding short-circuit surface during the cutting process. Simulation results show that the proposed waveguide achieves an electric field strength of 5.51 × 10⁵ V/m at 400 W input power, resulting in a 32-fold improvement in energy coupling compared to conventional WR340 waveguides. Microwave cutting experiments on ceramics and glass are conducted and compared with WR340 waveguide heating, with the double-ridged waveguide exhibiting significantly higher heating performance, showing a 93-fold increase in maximum temperature rise. This enables the precise cutting of alumina ceramics and glass sheets. A microwave heating simulation analysis of the temperature distribution on the cutting cross-section reveals that the heat source is concentrated in the center of the section, showing a more uniform and symmetrical temperature distribution compared to traditional thermal cutting. This study not only demonstrates the efficacy of the double-ridged waveguide in generating high-intensity electric fields but also offers a promising solution for low-power thermal fracture cutting of brittle materials, providing new insights for the future of advanced manufacturing technologies.