Simulation Study On The Fracture Mechanism Of Elastic Brush Deburring

Deburring is an indispensable process for metal blanking and processing,and it is also one of the technical difficulties that has always plagued sheet metal stamping companies.At present,there are many feasible methods for the deburring of flat stamping parts.When faced with complex shapes or tooth-shaped stamping parts,most deburring processes cannot achieve a complete deburring effect.A lot of practice shows that for this kind of stamping parts,the elastic brush made of silicon carbide and other materials is better than other methods in deburring processing effect,but few people have conducted in-depth theoretical research on the process of elastic brush deburring.Especially the research on the breaking mechanism of elastic brush deburring is very rare.The paper took a fine-blanking part of the drive gear of an automobile wiper as the research object,and carried out a simulation study on the mechanism of elastic brush deburring fracture.The main research conclusions are as follows:(1)Using DMI8 inverted microscope to measure the geometric parameters of the burr and the length of the small cracks at the interface between the burr and the part matrix for randomly sampled fine-blanking pinion parts.Basised on this,the Glitch model of two types of cracks,no damage and damage cracks,were established.(2)Through the method of elastic mechanics theory,the dynamic model of the interaction between the brush and the burr was established,the impact action of the brush was simplified to the form of impact load F,the theoretical expression of the mechanical model was deduced,and the burr model A qualitative analysis was carried out on the crack growth process.(3)The single factor test and orthogonal test numerical test of two burr models of non-damaged cracks and damaged cracks were carried out respectively.The results show that the best test combinations for the two burr models of non-damaged cracks and damaged cracks are F=15N,q_F=60°,Hc=0.070mm,and the residual burr height H is 0.084mm and0.005mm,respectively.(4)In the numerical simulation test of the brush model,some burrs didn’t propagate or did not fully propagate under a single impact load.Abaqus software was used to perform a low-cycle fatigue analysis numerical simulation test on the burr model.The relationship between the loading times and the crack propagation length was found to be a linear relationship.When the cyclic loading times was N=6,the crack could be fully expanded,indicating that the purpose of removing burrs has been achieved.(5)The optimal theoretical external load F obtained by orthogonal analysis was reversely loaded on the brush model,and the theoretical formula was derived from the relationship between the wire deformation angleθand the angular velocityωof the preset brush model;the value of the brush model is reversely loaded in the simulation test,the theoretical formula and the results of the numerical simulation test could be mutually verified.Furthermore,the motor parameters of the deburring test bench were calculated,which laid the foundation for the development of the bench test.The main research content of this paper provides theoretical support for the processing technology of sheet metal stamping burrs using elastic brushes,and provides an analysis method for the optimization of processing parameters of stamping burrs by brushes.The research results have important theoretical significance and practical application value for the process exploration and production of brush deburring.