PBO/BMI复合材料的霍尔推力器支架轻量化设计与力学性能研究OA

To enhance the lightweight performance and mechanical properties of Hall thruster brackets and overcome the limitations of conventional metallic materials in terms of specific stiffness,thermal conductivity,and weight reduction,the mechanical properties of poly(p-phenylene benzobisoxazole)fiber-reinforced bismaleimide resin(PBO/BMI)composites are systematically investigated,and the failure mechanisms are analyzed.Based on this material,the lay-up optimization and finite element simulations are conducted for the thruster bracket design.The bracket specimens are fabricated via compression molding,and their dynamic performance is validated through modal testing.The results indicate that the modified composites exhibited a 40.6% increase in the through-thickness compressive strength and a 30.4%improvement in the interlaminar shear strength,with superior tensile strength retention at elevated and low temperatures compared with unmodified materials.The measured mass of the Hall thruster bracket is only 0.62 kg,representing a 61.3%reduction relative to the design limit.The first natural frequencies of the assembly are in the range of 49.9 Hz to 123.0 Hz,satisfying the≥40 Hz design requirement,and the discrepancies between the simulation and experimental results are less than 3%.These findings demonstrate the feasibility of applying modified PBO/BMI composites in the lightweight structural design of electric propulsion components.