中文摘要：

研究了碳纤维增强聚酰亚胺树脂基复合材料MT300/KH420的高温力学性能,重点揭示了MT300/KH420的[0°]7、[0°]（14）和[±45°/0°/90°/＋45°/0°2]s层合板在常温-500℃的拉伸和层间剪切性能的变化规律。结果表明：在350℃以内,[0°]7层合板拉伸强度随温度升高有所提高,拉伸模量几乎不变,在420℃时拉伸强度和模量均出现明显下降,在500℃时分别保持在65%和83%以上,表现出优异的高温拉伸性能。MT300/KH420的[0°]（14）层合板层间剪切强度在常温-420℃随温度升高不断降低至52.8%,在高温下呈现出黏弹效应,且在420℃时最为明显。相比于单向层合板,[±45°/0°/90°/＋45°/0°2]s多向层合板高温力学性能较为稳定,且由纤维控制的纵向试件力学性能受温度影响较小。

英文摘要：

The high-temperature mechanical properties of carbon fiber reinforced polyimide resin matrix composites MT300/KH420 were studied,during which the tensile and interlaminar shear performance variation rule of MT300/KH420 laminates with[0°]7 ,[0°]14 and [± 45°/0°/90°/＋45°/0°2 ]s fiber orientations were especially analyzed at temperature ranging from ambient temperature to 500 ℃.Results show that tensile strength of [0°]7 laminate shows an increase while tensile modulus changes little with the increase of temperature until 350 ℃.At 420 ℃ tensile strength and modulus reduce significantly,and at 500 ℃,65% and 83% of their pristine values remain,exhibiting an excellent high-temperature tensile property.As temperature rises,interlaminar shear strength of MT300/KH420 laminates with[0°]14 degrades continuously from ambient temperature to 420 ℃ where a retention rate of 52.8% is observed.A viscoelastic effect occurs at high temperature,especially at 420 ℃ it turns to be the most severest. Compared with unidirectional laminates,[± 45°/0°/90°/＋45°/0°2 ]s multidirectional laminates show more stable high-temperature mechanical properties.Mechanical properties of fiber-dominated longitudinal specimen are less de-pendent on temperature.