Erosion Wear Performance And Mechanism Of Mold Materials

Erosion wear refers to the process of material removal on the surface of a workpiece caused by the impact of small particles enclosed in liquid or gas at high speed.Erosion wear is a common phenomenon in modern industrial production,which is an important factor causing failure and damage of workpiece.For example,in the plastic processing industry,filler materials added in plastic raw materials,such as silica sand,mica powder,titanium white powder,etc.,with the flow of the substrate,the mold is eroded at a certain speed or angle,causing the mold to wear and cause early failure.This paper studies the erosion process of impact particles on workpieces,reveals the mechanism of erosion wear,and clarifies the influence law of environmental parameters.It is of great significance to effectively control and reduce material wear,prolong the service life of workpieces and reduce the production cost of enterprises.In this paper,the finite element model of erosion process is established by numerical simulation method,aiming at the impact process of plastic filler particles on the surface of die materials.The erosion process of mould steel is studied,and the factors affecting erosion wear and the mechanism of material erosion failure are analyzed.The specific research contents and results are as follows.(1)The Johnson-Cook visco-plastic constitutive equation characterizing ductile materials is used to describe the behavior of materials during erosion wear.Based on the cumulative damage rule,a three-dimensional multi-particle erosion model is constructed,and the explicit erosion method is used to simulate the erosion process of the workpiece.In this paper,the erosion process of the 45 th steel and the variation of the stress in the process are analyzed.The morphology of the erosion pit is given,and the relationship between the surface removal volume and the particle impact number is summarized.(2)In this paper,the influence of environmental factors(erosion angle,erosion velocity and erosion temperature)and particle shape on the erosion wear of material surface is analyzed,the law of influence is revealed,the mechanism of erosion wear is clarified,and the main and secondary factors affecting the erosion wear rate of material are determined.It is found that the impact of erosion factors on material erosion wear is in the order of erosion speed,erosion angle,particle shape and erosion temperature,and the erosion speed is the main factor affecting material erosion wear rate.(3)The relationship between the change of particle kinetic energy and erosion wear on the surface of materials during particle impact was studied.Based on Hertz contact theory and energy conservation principle,the velocity change during particle impact on workpiece is analyzed,and shear energy factor and deformation energy factor are introduced.According to the energy consumption in erosion process,the erosion wear rate calculation formula is given.It is found that the energy loss of spherical particles increases with the increase of erosion angle,and the energy loss rate of abrasive particles with different shapes is different.