The Connecting Design And Process Analysis Of Composites Of Body Frame Structure Of The Electric Vehicles

At present,the connection methods of composite pipe structure such as mechanical connection and cementation are relatively mature,but they still have short plates.The connection of composite parts is the key to improve the utilization ratio of composite materials.A new connecting method of tube composite was proposed in this paper.This kind of connection adopts plastic and short fiber resin molded connectors to fix the carbon tube and makes use of carbon fiber sheet to wind and wrap the joint of the carbon tube and the connector,achieving a goal of making connection material completely metal-free.Specifically speaking,this paper put forward a carbon fiber tube connecting method.First of all,connector model was designed and its 3D printing manufacturing was performed so as to make short fiber resin molded connector.However,due to the small volume and space of samples,carbon fiber sheets were first wound on the carbon tubes that needed to be connected then vacuum bag molding process was performed and at last the carbon fiber tubes were put into the thermotank at 50-60? for an hour and a half to make them mold.Then eight samples were made based on the experimental method above.Among them,the connection materials of the compressed samples with 4/6/8 layers were ABS material.Besides,a six-layer sample adopting short fiber resin composite as connecting material was also manufactured.For comparison purpose,four bending samples were made with the same design methods of the compressed samples.Next,static compression and bending test were conducted on the eight samples to separately compare the influence of different layers and connecting materials on connecting performance.Moreover,the failure mechanism of the connection was also analyzed according to the failure forms of the samples in the test.Last,modeling and simulation were performed.Finite element analysis of the connecting construction was done on the basis of failure model and results of the experiment which verifies the feasibility of the modeling.Later,problems arisen in the process of sample making have been concluded and a more effective and convenient method to manufacture ideal samples was offered.Experimental results show that the valid peak loads of the eight-layer carbon fiber sheet covered static compression and bending test are 6732.52 N and 2190.46 Nseparately.And every added layer of carbon fiber sheet will lead to 600 N increase of valid peak load for the compression test while it is 200 N for the bending test.