湿热老化后碳纤维复合材料层间剪切强度实验方法对比研究

通过短梁法和双切口法研究湿热老化对T700/TDE-85复合材料层间剪切强度的影响,讨论两者吸湿规律随老化时间的变化关系,并对试件断口形貌进行分析。结果表明:两种试件吸湿规律均符合Fick第二定律,但两者平衡吸湿率和吸湿时间有所差别,双切口法试件的吸湿速率和平衡吸湿率均比短梁法试件高;双切口试件所测层间剪切强度受湿热老化影响比短梁明显,短梁试件每隔500 h层间剪切强度保持率为74.5%,61.0%,53.2%,50.6%,双切口每隔500 h层间剪切强度保持率为60.9%,38.3%,42.6%,33.0%;短梁试件失效模式随着湿热老化时间的增长变化比双切口更为复杂。

Comparison Study on Interlaminar Shear Strength Testing Methods of CFRP under Hygrothermal Aging Conditions

The effects of hygrothermal aging on the interlaminar shear strength of T700 /TDE-85 composites were studied by short-beam method and double-incision method.The relationship between moisture absorption and aging time was discussed,and the fracture surface morphology was analyzed.The experimental results show that the moisture absorption law of the two specimens is in accordance with Fickle's second law,but the saturated moisture absorption rate and moisture absorption time are different.The moisture absorp-tion rates and saturated moisture absorption rates of the specimens of double incision method are higher than those of the short beam method.The interlaminar strength of double-incision test is more obvious than that of short-beam under hygrothermal aging conditions, the interlaminar shear strength retention rates of short-beam method's specimens are 74.5%,61.0%,53.2% and 50.6% at 500 h intervals and the interlaminar shear strength retention rates of double-incision method's specimens are 60.9%,38.3%,42.6% and 33.0% at 500 h intervals.The failure mode of short-beam specimen is more complicated than that of double-incision with the increase of hygrothermal aging time.