DEM Based Simulation Of Micro Cracks And Micro Milling Of Glass

With the development of modern industry and scientific research, the glass has been widely applied in the machinery, building, automobile, aviation, optical and biological engineering, etc. At present, there are pieces of glass for precision machining and ultraprecision grinding, polishing, grinding and other processing methods, which mostly require long processing cycle, high cost and environmental pollution. If machining parameter selection is unreasonable, machined surface of the workpiece will apper cracks, surface damage and other defects. Therefore many scholars try to use cutting way instead of processing methods above. In this paper, by using the discrete element method(DEM) to simulate the propagation of the crack in the glass micro cutting process,and it provides the basis for reasonable selection of fine glass cutting parameters and improve the processing quality.The mainly work of this paper are as follows:(1)The Two/Three dimensional discrete element model of the quartz glass material is established through using the discrete element software PFC2D/3D which based on the fundamental principle of the discrete element method. Mechanical property parameters values of the discrete element model of glass is calibrated by the uniaxial compression test,Brazil split test and three point bending test. The paper got the two/three dimensional discrete element model of DEM matched with the mechanical property of quartz glass, and verify the feasibility of the discrete element method simulation of quartz glass..(2)Based on calibrated model, it has constructed the two-dimensional and 3D cutting model of quartz glass, and simulated two-dimensional cutting process and 3D milling process of quartz glass. The author analyzes the impact of cutting process parameters on the quartz glass cracks and cutting force in the cutting process. One group are obtained by optimizing the cutting parameters.(3)In the experimental platform which developed by our group, the quartz glass micro-diameter Ball Milling experiments are done by the author. The author analyzes the impact of micro-milling process parameters on the quartz glass milling force in the milling process, and establishes a set of parameters can be high surface quality and processing efficiency. At the same time the results of the simulation and experimental results of milling experiments were compared, the comparative result further demonstrates the effectivenessof the three-dimensional discrete element model of the quartz glass, and discrete element method to simulate quartz glass cutting process is reasonable.The results of this study provide a reference for the development and application of cutting glass, and provide a theoretical basis for improving the processing efficiency and optimizing the process parameters and proposes a new idea for the processing properties of glass materials, but also provide a new way for in-depth study of the mechanism of glass processing machinery.