This study introduces a novel sandwich-structured composite incorporating varying contents of zirconium diboride (ZrB 2 ), with polybenzimidazole (PBI) as the resin matrix and quartz fiber felt (QF) as the reinforcement. The ablative performance of the composites was assessed under high-energy continuous wave laser conditions, featuring a laser power density of 30 MW m -2 , and the laser ablation morphology and ablation mechanism of the ZrB 2 /PBI/QF composites were investigated. Further analysis examined the effects of ZrB 2 ceramic content on the density, thermal stability, mechanical properties, ablation characteristics, and rear surface temperature of the composites. Upon laser ablation, ZrB 2 oxidizes, forming a protective white ZrO 2 layer. At a 60% ZrB 2 content, the rear surface temperature of the composites reached 1031 °C after 42 s, resulting in a low linear ablation rate (0.12 mm s -1 ). The gases and residual carbon produced by the pyrolysis of PBI resin, the melting of QF, and the release of SiO 2 gas contribute to the formation of a SiO 2 protective layer. Building on this foundation, the incorporation of ZrB 2 further enhances energy dissipation and facilitates the development of a ZrO 2 -SiO 2 protective layer with increased reflectivity. This layer, along with another oxidation product, B 2 O 3 gas, serves to isolate oxygen and mitigate erosion. The findings suggest significant potential for developing advanced materials for high-energy continuous wave laser protection.
In this work, poly- p -phenylene benzobisoxazole (PBO) fibers reinforced polybenzimidazole (PBI) resin-based laser ablation composites (thickness = 5 mm) with different SiC contents were prepared. SiC/PBI/PBO composites exhibited good mechanical properties , excellent thermal stability and laser ablation properties. The laser ablation properties and ablation mechanism of the composites were investigated using a high-energy continuous-wave laser (30 MW·m −2 ). Increasing the SiC content led to increase in composites density, while decreasing the bending performance of the composites. However, it improves the mass and linear ablation rates, resulting in an overall improvement in ablation properties. At a SiC content of 70 %, the composite exhibited a mass loss of 8.2 %, a mass ablation rate of 9.2 mg·s −1 , and a linear ablation rate of 0.11 mm·s −1 . The ablation process of SiC/PBI/PBO composites was delineated into pre-ablation and post-ablation stages, with the ablated composites divided into the ablation center, transition region, and outer region based on morphological characteristics. After ablation, numerous white hollow SiO 2 spheres and SiO 2 protective layers were formed in the ablation centers, the transition regions were deformed and cracked, while the outer region remained unscathed.
危险品化学品经营许可证（带存储）