不同工艺碳纤维增强复合材料构件的力学性能

针对碳纤维增强复合材料在电动汽车车身上的应用,分别采用手糊、真空袋压和模压三种成型工艺,设计制备了碳纤维增强复合材料层合板和双帽形管件两种实验样件。对样件进行了单向拉伸和三点弯曲试验,对构件的力学性能、表面质量、微观结构和破坏形式进行了比较,并分析了不同工艺性能存在差异的原因。研究表明:采用模压工艺成型的复合材料结构件气泡少,孔隙率小,表面质量最好;模压成型的层合板拉伸强度比手糊成型的提高了14.39%,管件弯曲强度比手糊成型管件提高了一倍,比真空袋压成型管件提高了47.58%。研究证实模压成型相对于手糊和真空袋压工艺,产品具有较优良的力学性能和一致性,较适合于电动汽车等轻量化结构的成型。

MECHANICAL PROPERTIES OF CARBON FIBER REINFORCED PLASTIC STRUCTURES WITH DIFFERENT FORMING PROCESS

Two carbon fiber reinforced plastic (CFRP) structures were prepared by hand lay-up process,vacuum bag pressure process and compression molding process.The effects of forming process on the mechanical properties and forming quality of CFRP structures were investigated based on tests and cross-section morphology observation.For the application of CFRP in the electric vehicle,two typical kinds of structures,laminated plates and double-cap tubes,were designed and prepared by different process.The tensile and three point bending tests were carried out,and the mechanical properties,surface qualities,microstructures and failure modes of structures were compared.The results indicate that the composite structures made by compression molding process have better quality with fewer bubbles and smaller porosity.The tensile strength of CFRP laminated plate made by compression molding process is about 14.39％ higher than hand lay-up laminated plate.The bending strength of tubes is twice of hand lay-up tubes,and is 47.58％ higher than vacuum bag pressure tubes.It is concluded that the CFRP structures prepared via the compressing molding process have higher mechanical properties and better consistency than the other process,it is more suitable for the application on the electric vehicle and other lightweight structures.