Experimental Study Of Tool Wear In Diamond Cutting Of Optical Glass

Recently, with the rapid development of advanced technology, optical glass has been widely used in photoelectron, nuclear energy, aerospace, communication, laser technology and so on. Glass is a hard and brittle material, which possess the characteristic of high hardness, high brittleness, low fracture toughness and poor machinability. Conventional machining process such as grinding and polishing was applied to glass fabrication prolonged for hundreds of years, however, these conventional process do not meet the demands of today's precision engineering, which require both fast production rates and high quality surfaces of complex shapes.With the development of the precision and ultraprecision machining technology, ultrasonic vibration diamond cutting has become the main research direction of precision machining of brittle materials, for the technical superiority of this technology. In this paper, emphasis was placed on characteristics and mechanisms of tool wear in diamond cutting of optical glass. The phenomena and rules of the tool wear were observed and analyzed, based on the experiments of the influence of cutting parameters, vibration parameters and cutting fluid on tool wear, and then researched the effective method to reduce the tool wear, according to optimizing the cutting parameters and changing the cutting conditions.Firstly, this paper summarized the current situation of the ultrasonic vibration machining technology, the technology of cutting brittle materials in ductile regime, the tool wear mechanism of diamond cutting and the principle of cutting fluid in diamond cutting, at home and abroad.In order to observe the phenomenon of tool wear, and understand the effect of cutting parameters and vibration parameters on tool wear, this paper designed the orthogonal experiments of four factors and three levels, with rake angle, spindle speed, feed and ultrasonic amplitude as the factors, and three diamond tools were chosen, according to orthogonal design method and the actual processing conditions.Afterwards, orthogonal experiments of three optical glasses were carried. The laser canning confocal microscope was employed to measure the tool's two-dimensional, three-dimensional topography and the wear width of the tool wear of diamond tools, and then the range analysis method was used to analyze the experimental results and conclude the rules of the cutting factors influence on the tool wear. Meanwhile, this analysis also was the foundation of the research of tool wear mechanism and subsequent experiments of research the cutting fluid influence on the tool wear.After analyzing the features characteristics of tool wear, this paper concluded the main mechanism of tool wear in diamond cutting of glass was mechanical wear. And then, the test of research on the influence of cutting fluid on diamond cutting of glass assisted ultrasonic vibration was proceed, referring to the optimum parameters obtained by the orthogonal experiment, afterwards, this paper discuss the influence of cutting fluid on diamond cutting of glass, based on the action principle of cutting fluid. The results show that the proper selection of cutting fluid could restrain tool wear and enhance durability of diamond tool.