热空气老化对PBO/T700层间混杂复合材料力学性能的影响

EFFECT OF HOT AIR AGING ON MECHANICAL PROPERTIES OF PBO/T700 HYBRID COMPOSITES

分别利用材料万能试验机和DMA研究了热空气老化对PBO/T700层间混杂复合材料静态力学性能和动态力学行为的影响。静态力学性能测试结果表明,经热空气老化不同时间后,PBO/T700层间混杂复合材料的拉伸强度和压缩强度均出现了一定程度的下降,最大降幅分别为12.7%和6.9%,拉伸模量从126 GPa增大到145 GPa,弯曲强度、弯曲模量和层间剪切强度变化较小。DMA测试结果表明,热空气老化使PBO/T700层间混杂复合材料的耐热性和刚性提高,随着老化时间的增加,E'向低温方向移动,E″向高温方向移动,说明复合材料的耐热性和刚性又开始下降。

The effects of hot air aging on static and dynamic mechanical properties of PBO/T700 hybrid composites were studied in this paper by using a universal testing machine and dynamic mechanical analysis（ DMA）.The static mechanical properties testing results indicate that the tensile strength and compressive strength of PBO/T700 hybrid composites declined after hot air aging,with maximum drop of 12. 7% and 6. 9%,respectively. The tensile modulus increased from 126 GPa to 145 GPa,while the flexural strength and modulus and the interlaminar shear strength of the composites show little changes. The DMA result shows that the heat-resistance property and rigidity of PBO/T700 hybrid composites increased to some extent after hot air aging. However,the E＇ and E″ of the composites shift toward low temperature and high temperature,respectively,with the increase of the aging time,which means some decline of heat-resistance property and rigidity of the composites.