高空低温环境对无人机复合材料及夹芯结构性能的影响

Performance Research of UAV Composite and Sandwich Structure at High-altitude Cryogenic Conditions

针对高空长航时无人机UAV面临的-82℃低温环境,开展低温温度对T700/LT-03A复合材料及夹芯结构的性能影响研究。研究结果表明,低温下复合材料及夹芯结构强度均随温度降低而升高,T700/LT-03A复合材料-82℃时的拉伸强度为2 500 MPa、层间剪切强度为115 MPa、冲击损伤强度CAI保持在150 MPa。其原因是低温下碳纤维的横向收缩比树脂基体小,界面摩擦力得到增强,从而获得高的界面粘接强度。-70℃低温循环后泡沫和蜂窝夹芯结构强度剪切数据分别为2.6 MPa、2.2MPa。低温试验结果表明T700/LT-03A复合材料及夹芯结构在低温下保持了较好的整体承载能力。

On the basis of cryogenic conditions about the HALE-UAV,this paper analyzes the performance of T700/LT-03A composites and sandwich structure at high-altitude cryogenic conditions.The results prove that the mechanical properties of the composite and sandwich at temperature are better than those at normal temperature.When the temperature falls to-82℃,the tensile strength value of T700/LT-03A composite is 2 500 MPa,interlaminar shear strength is 115 MPa,residual compressive strength CAI after impact maintain at 150 MPa.The reason analyzed in this paper is that the transverse shrinkage of carbon fiber is smaller than that of resin,so the interface friction force is augmented and higher interface bond strength is attained.The shear strength data of foam and honeycomb sandwich structures were 2.6 MPa and 2.2 MPa at-70℃alternating,respectively.Low temperature test results show that the T700/LT-03A composites and sandwich structures have good overall bearing capacity.