Experimental Study On Drilling Simulation Of Carbon Fiber Composite Material

Due to its high strength,good heat resistance,corrosion resistance,thermal shock resistance and low thermal expansion coefficient,carbon fiber composite materials have been widely used in sports machinery,chemical machinery and medical fields in recent years.However,in practical applications,the mechanical processing of carbon fiber composite materials is difficult,especially in the processing process that requires a lot of hole processing,and it is difficult to ensure the processing quality.Therefore,it is of great significance to study the stress conditions of the drilling process.Firstly,starting from the cutting of carbon fiber composite materials,a cutting model was established,and the quality of the machined surface obtained under different lamination angles and cutting angles of the tool was analyzed,and the critical axial forces of the two tools were calculated.Secondly,using laminates as the research object,the stress-strain relationship of orthotropic materials was analyzed.The damage model based on the Hashin damage criterion was established and the damage evolution process was deduced.Finally,according to the problems in the drilling process,the finite element simulation software ABAQUS was used to simulate the process of twisting the laminated plate with twist drill and thin plate drilling.The meshing and material properties of the laminated plate and tool were respectively designed.In the ABAQUS software,the assembly was completed and other pre-processing was set.Afterwards,on the basis of simulation experiments,four-factor and multi-level orthogonal tests were designed.Several of the effects on the machining quality in the drilling process were compared.Important factors are analyzed one by one.Afterwards,the drilling test was designed,and the conclusions obtained were compared with the conclusions of the simulation test,thus verifying the reliability of the simulation test.According to the analysis of the results,compared to the twist drill,the use of thin-plate drilling can obtain better processing quality;in order to improve the processing quality,the cutter with smaller diameter should be selected properly when drilling;on the basis of single variable,continue to increase the variable The law between the drilling parameters and the change of axial force is obtained.The results show that the axial force increases with the increase of the feed speed and decreases with the increase of the spindle speed;the shear damage of the layers of the laminate is obtained.Observing and contrasting the situation,it was found that the shear damage of the first layer and the fourth layer is more obvious,and the damage range of the material will increase with the increase of the feed speed.In addition,the first layer of the simulation results can be reasonably explained by the cutting theory.Tear phenomenon.