Modeling and experimental investigation on microwave transmission characteristics of glass fiber‐reinforced plastic ablated by continuous‐wave laser

Abstract The article studies the electromagnetic behavior of Glass Fiber‐Reinforced Plastic (GFRP) under high temperatures using continuous high‐energy laser ablation (CW), by the theoretical and experimental approaches. The theoretical model is proposed to predict the electromagnetic properties of GFRP ablated by laser. Based on the principles of heat transfer, a temperature model for the material was developed, which couples with reaction kinetics and is used to predict transformations in the state of the material. Subsequently, the variations in electromagnetic microwave parameters are predicted. This approach establishes a direct theoretical link between temperature and the fluctuation of electromagnetic microwave properties. Experiments tested the data changes on the electromagnetic properties of the material under different heating times, including the transmittance and reflectance of visible and infrared light, microwave characteristics of different frequency bands, and Raman spectra of different ablation times and sample depths. The results indicate the temperature theory and electromagnetic properties change models are consistent with the actual physical process with high accuracy and provide comprehensive temperature–electromagnetic performance data for these materials. Furthermore, graphitized carbon is the main reason affecting the material's microwave absorption rate and transmittance. The homogenization degree of the material, internal microstructure, the material's surface morphology, and color will also further affect the material's transmittance, reflectance, and absorption rate. The results of this article provide a reliable theoretical model and temperature–electromagnetic performance data for addressing similar issues, which is of reference significance for improving the high‐temperature resistance of GFRP and enhancing its electromagnetic performance. Highlights A direct link between temperature and material electromagnetic microwave properties was established. A laser ablation model was established. Microstructural changes in materials were confirmed to affect microwave parameters. The impact of three‐dimensional distribution of carbide products on microwave transmission was analyzed.