Study On The Grinding Mechanism Of Glass Ceramics During Single And Multiple Scratches

Glass ceramics have a wide range of applications in the field of national defense,architecture, energy, medical and daily life owing to its excellent mechanical, thermaland chemical properties. Glass ceramics are a kind of hard and brittle material whichpossess the nature of non-crystalline such as glass and crystalline such as ceramics.Grinding is the main method for processing this hard and brittle material. However, itis easy to bring in surface and subsurface damage when using grinding. Gettinghigh-quality of the workpiece is not easy, which has limited the development andapplication of glass ceramics in various fields.The grinding mechanism of glass ceramics was studied by utilizing single-gritand multiple-grits tools to conduct a series of single and multiple scratchesexperiments. The material removal mechanism and crack propagation of glassceramics were investigated. The main contents of this paper are as follows:1. Single-grit and multiple-grits tools were designed according to the relevantultra-precision grinding characteristics. FIB (focused ion beam) systems wereutilized to fabricate the tools. The ultra-precision experimental systems were setup.2. Using single-grit tool to conduct single scratch tests under various cutting depthson the machine with nano-precision. The white light interferometer, ultra-depthmicroscope and SEM (scanning electron microscopy) were used to observe thesurface and subsurface of materials. The surface morphology, material removalrate, cracks propagation on the surface and subsurface of the material, thedistribution characteristics of the radial cracks were analysed.3. The single-grit tool was used to conduct a series of double scratch experimentsunder different cutting depths and scratch separations. The results showed that theinteraction between double scratches was closely dependent on the scratch depthand separation distance. A parabolic could be used to describe the relationshipbetween the material removal rate and the separation distance. The materialremoval rate was greatly improved owing to the interaction between doublescratches. Using the triple-grits tool to conduct a series of experiments under various cutting depths. By comparing the crack propagation of double scratchesby single-grit tool and triple scratches by triple-grits tool, it can be inferred thatmaterial peeling is the interaction of lateral cracks and radial cracks whenseparation distance is small. But when separation is large enough, the materialpeeling is only the interaction of radial cracks.In this paper, the grinding mechanism of glass ceramics by single andmultiple scratches was studied to shed a light on the material removal mechanismand crack propagation of glass ceramics, which has provided a basic theory forobtaining a high surface quality of glass-ceramic device.