PEK-C膜层间增韧碳纤维/环氧树脂复合材料的力学性能

Mechanical properties of PEK-C interlayer toughened carbon fiber/epoxy composites

为探究热塑性酚酞基聚醚酮(Polyaryletherketone with Cardo,PEK-C)树脂薄膜及膜厚对层间增韧碳纤维/环氧树脂复合材料力学性能的影响,利用浸渍提拉法制备了三种不同厚度(分别约为1μm、10μm、30μm)的PEK-C膜,通过热压成型制备了层间增韧碳纤维/环氧树脂复合材料层合板,对其进行了Ⅰ型层间断裂韧性、冲击后压缩强度、层间剪切及弯曲性能测试,并利用SEM观察微观形貌及AFM扫描微观相图。结果表明:不同PEK-C膜厚增韧碳纤维/环氧树脂复合材料的Ⅰ型层间断裂韧性、冲击后压缩强度及层间剪切强度有不同程度提高,Ⅰ型层间断裂韧性及层间剪切强度以膜厚为10μm最佳,分别增大了157.17%和17.57%,冲击后压缩强度以膜厚为30μm最佳,达到了186.67MPa,这是由于PEK-C与环氧树脂在热压固化过程中形成了双相结构,改善了材料韧性;但弯曲性能持续下降,强度及模量由未增韧的1 551 MPa、106 GPa分别降至30μm时的965MPa、79GPa,这是由于PEK-C树脂扩散进入环氧树脂中,降低了纤维体积分数及材料刚度。

The thermoplastic resin polyaryletherketone with cardo(PEK-C)films of three different thicknesses(about 1μm,10μm,30μm)were prepared by dip-coating method.Hot pressing technology was employed to obtain the film interleaved carbon fiber/epoxy composite laminates.The mode Ⅰ interlaminar fracture toughness(GIC),compressive after impact(CAI),interlaminar shear strength and flexural properties were tested to investigate the effect of PEK-C film and film thickness on the mechanical properties of carbon fiber/epoxy composites.The microstructure was observed by SEM and the phase structure was scanned by AFM.The results show that GIC,CAI and interlaminar shear strength increase for the carbon fiber/epoxy composite laminates with PEK-C films of different thickness.GICand shear strength are increased maximally at a film thickness of 10μm,which are increased by 157.17% and 17.57%,respectively.CAI is the largest at a film thickness of 30μm,reaching 186.67 MPa due to the fact that PEK-C and epoxy resin form a dual-phase structure during the hot pressing curing process,improving the toughness of the material.The flexural strength and flexural modulus of carbon fiber/epoxy composite laminates decrease with the increase of the film thickness,from 1 551 MPa,106 GPa without films to 965 MPa,79 GPa at the film thickness of 30μm due to the diffusion of PEK-C resin into the epoxy resin,which reduces the fiber volume fraction and material stiffness.