Study On The Effect Of RTM Injection Resin On The Deformation Of Laminated Fabrics

The bond between the composite resin matrix and the fiber reinforced material is high,so the product has good performance.However,RTM molding process is a closed mold operation process,and the fiber flow in the mold cavity,fiber impregnation process and resin curing process all have a great impact on the performance of the final product,which leads to the complexity and uncontrollability of the process.Defects in RTM process usually occur in the resin filling stage,in which "fiber scouring" is the scouring deformation of the preform caused by the excessive glue injection pressure of the resin.Therefore,a series of work has been carried out in this paper to study the erosion and deformation of the laminated fabric in the process of resin injection into the mold cavity.(1)First of all,a visual experiment was carried out on the process of resin adhesive injection by designing a visual abrasive.The results showed that during the process of resin adhesive injection,excessive resin pressure would cause erosion deformation on the fabric,but the fabric deformation only occurred in the wet fiber part after being soaked by the resin,and the fiber that was not soaked by the resin would not be deformed.Then by changing the number of layers to observe the erosion deformation of the fabric,it is found that with the increase of the number of layers,the erosion deformation of the fabric also increases the pressure of injection.(2)Then,based on the visualization experiment,the interaction between the dry and wet lay fabric and the mold cavity is studied.Through the design of tension fixture,compression fixture and pressure sensor,the friction coefficient between the dry and wet fabric and the mold cavity and the stiffness of the fabric in the mold under different layering number were tested.The results show that the friction coefficient between the fabric and the mold cavity and the stiffness of the fabric in the mold increase with the increase of the number of layers,and the friction between the fabric and the mold cavity decreases due to the lubricating effect of resin.The friction coefficient between the wet ply fabric and the mold cavity is expressed qualitatively as a function of the Hersey number.The friction coefficients between the 10,11,12 and 13 dry fabrics and the cavity are 0.135,0.139,0.144 and 0.148,respectively.(3)Finally,the composite laminates and the undeformed composite laminates were prepared according to the in-mode stiffness of the wet laminates.The tensile properties,bending properties and compression properties of the laminates were tested,and the influence of the fabric deformation on the mechanical properties of the composites was analyzed.The results show that the deformation of the fabric results in different fracture of the fiber under the action of external force,so the mechanical properties of the composite material are significantly reduced by the deformation of the fabric.