Study On Drilling Damage And Processing Method Of Alumina Ceramics

As a typical hard and brittle material,engineering ceramics have excellent mechanical properties,ultra-high hardness and excellent chemical properties,which enable them to be widely used in industrial fields and 5G construction.However,the material characteristics of high hardness and high brittleness make it difficult to control the processing quality of engineering ceramics.Especially in the drilling processing of high hardness engineering ceramics such as alumina ceramic,the breaking edge of the hole and the damage of its wall almost exist at the same time.How to control the damage in the processing of holes in ceramic materials and improve the processing quality has become a key issue that has attracted much attention from researchers.In this study,by simulating the drilling process of alumina ceramic based on discrete element method,the processing damage and processing mechanism of the ceramic hole are studied,and the use of pecking drilling and the bottom cushion in drilling are proposed to reduce the drilling damage.Meanwhile,a series of drilling experiments are carried out to verify the simulation results.The main content of this article includes the following aspects:(1)The apparent morphology of diamond tool was observed,and the morphology of abrasives was simply classified.In addition,based on the discrete element method,the alumina ceramic workpiece and the 3D simulation model of diamond tool with different abrasive grain morphologies and abrasive parameters were established and calibrated,and the alumina ceramic drilling simulation model was built in this paper.(2)The discrete element simulation of alumina ceramic drilling was carried out systematically,and the orthogonal drilling simulation of alumina ceramics was carried out based on the diamond tool model with different abrasive grain morphology,different abrasive grain protrusion heights and abrasive grain inclination angles.The damage of the workpiece model under different drilling processes in the simulation process was observed,and the changes in the drilling force,the damage observation,and the hole formation after processing analyzes in this paper.(3)Through drilling experiments on alumina ceramics,the damage of workpieces and drilling tools in the drilling process was explored,and the influence of different processing parameters on the quality of drilling was summarized.In addition,the damage of ceramic hole and diamond tool were observed and analyzed.(4)Two different processing methods for drilling alumina ceramic hole are proposed,including pecking drilling and the use of bottom cushion.The optimized DEM processing model is established and the drilling simulation results of different processing methods are compared,and explored the processing damage of the exit of ceramic hole under different processing technologies.At the same time,drilling experiments of alumina ceramics under different processing methods were also carried out.By observing the damage of diamond tool and ceramic workpieces,the advantages and disadvantages of different processing technologies are explored.Based on numerical simulation and experimental research,this paper explores the influence of different processing methods and abrasive grain morphology on the drilling damage of alumina ceramics,and studies its processing method.The research content of this paper is expected to further improve the drilling processing of alumina ceramics.The damage mechanism of the workpiece provides guidance for optimizing the quality of engineering ceramic drilling.