Experimental Study On Automatic Laying Forming Technology And Process Of Carbon Fiber Structural Parts

The automatic lay-up technology of high performance Carbon Fiber Reinforced Polymer(CFRP)is a key technology for the manufacturing of advanced composite materials,and the regulation of lay-up process parameters is an important link to achieve high performance manufacturing.The research in this field is still in its initial stages,so it is necessary to carry out research on the lay-up equipment and process of the CFRP automatic lay-up process.In this thesis,the design of a CFRP automatic lay-up system is completed with the background of automatic lay-up of composite components and the research object of domestic carbon fiber unidirectional prepreg;the research on the influence of lay-up process parameters on the quality of lay-up formed preproducts is carried out;the influence of layup process parameters on the bonding performance between prepreg layers is explored;and the research on the influence of lay-up process defects on the performance of formed products is completed.The main contents are as follows:(1)Complete the design of the CFRP automatic lay-up system.Determine the composition and laying principle of the CFRP automatic laying system;design the structure of the laying head in the main components of the system;determine the internal structure according to the working principle of each module;complete the overall scheme design of the CFRP automatic laying system;design the control scheme according to the laying principle of the prepreg bundle,and complete the construction of the automatic laying system.(2)To complete the study of the influence of lay-up process parameters on the apparent quality of the laid preforms.Single-factor experiments were conducted using the experimental platform to analyze the effects of lay-up temperature,lay-up pressure,and layup speed on the automatic lay-up quality.The mathematical models of the three process parameters were established using the Box-Behnken response surface method to obtain the combination of process parameters under the optimal apparent quality and the process parameters corresponding to the maximum production efficiency under the acceptable layup quality.(3)To complete the study on the interlayer bonding performance of prepreg filament bundle lay-up under different process parameters.Simulate the laying process using the automatic laying process parameters experimental platform,design mandrel peeling experiments to investigate the effect of laying process parameters on the interlayer adhesion of prepreg,design orthogonal experiments to derive the primary and secondary order of process parameters affecting the interlayer bonding performance of prepreg,and obtain the process parameters corresponding to the maximum bonding performance between prepreg laying layers under the premise of ensuring the laying quality of preproducts.(4)To complete the research on the influence of lay-up process defects on the performance of formed specimens.Using unidirectional laminate as the research object,a prepreg lay-up model was established to predict the deformation size of prepreg transverse deformation under two sets of process parameters;the transverse deformation of the automatic lay-up process was verified through experiments,and the common types of defects caused by deformation were analyzed;CFRP automatic lay-up equipment was used to form defect-free,gap,and stacked specimens,and the thickness,tensile,and bending properties of the specimens were measured to obtain the effect of defects on the performance of the formed products.The effect of defects on the mechanical properties of molded products was measured.