| High-speed grinding was recognized as an high-efficiency and high-quality processing methods in the modern industry. In the process of High-speed grinding, the workpiece and the abrasive grains kept high-speed crashing each other, the energy which was confined to a micro-region under the transient force causes the material with a local high temperature, and the material may reach molten or close to molten state, the resulting of many new mechanism and the action mechanism about surface integrity need to be studied urgently. The grinding processing was the combined effects of many grits which was discretely distributed around the wheel surface completed swiping, plowing and cutting processing, a variety of physical and mechanical phenomena emerged during this processing and the mechanism was complex. The single grain cutting which was considered as the basic mode of grinding was becoming an important means of understanding the complexity of the grinding action. The ultrasonic vibration processing which owned those characteristics such as energy concentration, instantly action and fast cutting that can effectively change the cutting mechanism of traditional processing and get a unique process results. This paper was working on the theoretical and experimental study of a single Cubic Boron Nitride CBN abrasive under high-speed grinding with Ultrasonic-assisted, this grinding technology combines the characteristics of high-speed processing and ultrasonic processing. The study includes the following aspects:(1)Taking the characteristics of ultrasonic vibration system and the requirements of high-speed grinding system into consideration, a set of test equipment of high-speed grinding of single grain with ultrasonic-assisted was developed and this equipment based on ourselves laboratory existing equipment. Transformed a workpiece-toolholder system which can be connected to the machine spindle basised on the standard tool holders. Workpiece size has been designed in order to meet the requirements of high-speed grinding, and the dynamic balance of the workpiece-toolholder system has been debugged. After debugged the workpiece speed can reach 15000r/min, line speeds up to 160m/s and the workpiece runout can be controlled within 2μm.(2)The kinematics and grinding characteristics of the single grain under high-speed grinding with ultrasonic-assisted which we getted that is based on the analysis of the single grain grinding trajectories. Comparated and analysised the cutting path length, the cutting groove width and the average chip area under ultrasonic-assisted and ordinary high speed grinding, we can get that the cutting path was more lengther,the cutting groove was more widther and the average area was smaller during the high-speed grinding of a single grain with ultrasonic vibration.Finally, we calculated the critical cutting speed of a single grain in the form of axial vibration of cylindrical grinding.(3)Grinding force measurement model of a single grain was established and the cutting force was studied experimentally based on the analysis of grinding characteristics and kinematics about a single grain with ultrasonic-assisted. The results showed that the grinding force can be reduced under ultrasonic-assisted high-speed grinding and there was a wider processing range, what’s more, the ultrasonic-assisted grinding can also improve processing efficiency.(4)To study the characterization method of abrasive wear and explore the main wear form of single abrasive under ultrasonic-assisted high-speed grinding, we taked these three aspects which were the grit protrusion height, the area ratio of abrasive wear and the signal characterization of grinding force into consideration, finally, we reached the influence law about the geometric morphology parameters of single grain and grinding parameters of the grinding process to abrasive wear. |
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