Research On Erosion Wear Of Plastic Filler Particles On Mold Materials

Erosion wear is very common in the processing of engineering plastic products.During the processing of engineering plastics,the surface of the mold cavity under the action of erosion plastic filler particles,often defects such as pitting occurred.The surface flaws of the mold severely affect the quality of plastic products,and it is also an important factor that causes premature failure of the mold.Study and master the erosion wear law of molds,to reduce the erosion wear of the mold as much as possible,which not only helps to ensure the quality of plastic products,but also prolongs the use time of the mold.In this paper,with the help of ANSYS/LS-DYNA software,a finite element model of plastic filler particles impacting mold materials is established.This model simulates the dynamic impact process of particles on the mold surface,analyzes the erosion morphology of the target surface after the particles impact.At the same time,the law of energy change in the impact process is studied,and the impact speed and angle of impact on the law of energy change are analyzed.Finally,based on the characteristics of energy dissipation in the impact process,a calculation model for predicting the erosion wear rate is established.The research content and results are as follows:(1)Using ANSYS/LS-DYNA dynamic analysis software,an explicit dynamic model of particles impacting the target is established.The Johnson-Cook material constitutive equation and cumulative failure criterion are used to describe the mechanical properties of the material,and both single particle and multiple particles impact models were constructed.The impact dynamic process of a single particle impacting the target material is analyzed,and the failure mechanism of the target material is analyzed by combining the impact morphology and the impact process of multiple particles.(2)By simulating the erosion wear process of particles on the material,the law of energy change during the impact process is studied,and the erosion wear mechanism is revealed.Studies have shown that when the impact angle is constant,as the particle impact velocity increases,the impact energy absorbed by the target material increases,and the target material wears more severely;When the impact velocity is constant,as the particle impact angle increases,the energy loss rate of the particles continues to increase;When the particle impact angle reaches 90 degrees,the energy loss rate of the particles reaches the maximum;The critical speed of target wear is related to the impact angle of the particles,which gradually decreases as the impact angle increases;During the multiple particles impact,work hardening occurs in the impacted area.As the number of impacted particles increases,the depth increment of the erosion pit gradually decreases,and the energy loss rate of the particles also gradually decreases.(3)On the basis of deformation wear theory,according to the characteristics of energy changes during the impact process,considering the properties of target material,impact parameters and energy factors and other factors,a prediction model of target erosion and wear rate based on energy dissipation is established.The calculation results of this model are consistent with the finite element simulation results,indicating that the model can better predict the wear of filler particles on the target.