考虑温度环境下树脂基复合材料力学性能及模型研究

采用试验的方法研究了T300/QY8911-Ⅳ复合材料不同温度环境(室温、160,200,260℃)下的纵向拉伸、横向拉伸及面内切变力学性能,探讨了材料的模量、强度随温度变化的规律并提出了相应的力学模型.试验结果表明:在室温至200℃复合材料纵向拉伸模量、强度受温度影响较小,拉伸模量最大变幅为2.82%,强度为1.41%;当温度升高到260℃时,由于树脂基体变质,材料纵向拉伸模量与强度均下降,模量下降5.85%,强度下降7.01%(均相对200℃);横向拉伸和面内切变模量、强度受温度的影响较大,在160℃范围内,材料的平均模量分别下降了49.21%和70.34%,强度下降了38.49%和44.85%.当温度升至200℃时,材料的横向拉伸及面内切变模量与强度进一步下降,模量降幅为25.13%和38.30%,强度降幅为0.41%和15.95%.拟合结果表明:3个力学模型均适用于不同温度、载荷类型下的数据分布规律,但模型Ⅱ与模型Ⅲ对数据的拟合更准确. 

Study on mechanical properties of resin composites and models considering temperature environment

The longitudinal tensile, transverse tensile and in-plane shear mechanical properties of T300/QY8911-Ⅳ composites were initially investigated at different temperatures (room temperature,160,200,260℃).The variation rules of modulus and strength as the function of temperature were then discussed, and the corresponding mechanical models were proposed.The test results showed that the longitudinal modulus and strength were less affected by temperature at the range of 200℃. The maximum amplitude was only 2.82% and 1.41%, compared with the average value (room temperature). Due to the resin matrix deterioration, the longitudinal tensile performance was decreased by 5.85% and 7.01% (260℃),respectively. The properties of transverse tensile and in-plane shear were significantly affected by temperature. The modulus of transverse and in-plane shear were reduced by 49.21%,70.34% and the corresponding strengths declined by 38.49%, 44.85% (160℃) with respect to the average modulus (room temperature). The modulus properties mentioned above continued to decline by 25.13%, 38.30% (200℃) and the strength dropped by another 0.41%,15.95%, respectively. The fitting results manifest that the three mechanical models are suitable to fit the data obtained by different temperatures and loads, while the model Ⅱ and Ⅲ are more accurate.