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There has been increased interest in the use of advanced ceramic materials such as silicon carbide in the recent past, due to its unique physical and mechanical properties. However, the increase of the machining rate relies on the understanding of material removal mechanism on the microstructural scale and the relationship between the grinding characteristics and formation of surface/subsurface machining-induced damage. In this paper, grinding characteristics and surface integrity of SiC ground with diamond wheel on cylindrical grinding machine have been investigated. The grinding chip and the ground surface damage have been studied with scanning electron microscope (SEM). In particular the residual stress distribution has been analyzed by a single exposure technique d - sin2 (Ψ) method with the aid of powder X-ray diffractometer.

In order to reconcile the contradiction between the ceramic grinding efficiency and surface integrity, high-speed grinding with diamond grinding wheel is supposed to be a solution. In this paper, first of all, a normal grinding force model is proposed based on the consideration of the material property and the grinding process parameters. It can be seen that an elevated grinding wheel velocity in combination of a higher workpiece speed can increase the machining rate while maintaining the desired surface integrity. After a series of grinding tests, a comprehensive measurement has been done to study the surface damage by the surface roughness, the microscope profile and the X-ray diffraction. In particular, the effect of the grinding parameters on the ground surface are analyzed and reported.

The surface quality of workpiece depends largely on workpiece surface temperature in grinding. The key parameters on workpiece surface temperature calculation model have been researched and the calculation model constructed in this paper, including the convective heat transfer coefficient (CHTC) (hf), heat flux (qch) and the grain contact half-width (r0) which are assumed to be constant in workpiece surface temperature model given by Rowe. And the improved Rowe model has been proposed (Rowe/Li model) which not only involves the grinding process parameters such as the speed of wheel and workpiece, but also the geometric parameters of workpiece, grinding wheel and abrasive. The experimental results of the surface temperature in high-speed grinding are very close to the results by Rowe / Li model. Relative to the Rowe model, the obtained surface temperature by Rowe / Li model has decreased by about 35-40%. Under the conditions of the same material removal rate, high-speed grinding, namely, increasing wheel speed can effectively reduce the surface temperature and improve the grinding quality.

This paper presents the effects of spindle system configuration on the dynamic and static characteristics of high speed grinding. A 3D physical mode of high-speed grinding motorized spindle system with rotation speed of 150m/s was provided. The motorized spindle system consists of bearings, rotor, stator, spindle housing and grinding wheel. Based on the finite element method (FEM), the static characteristics, dynamic and the transient response are analyzed based on the finite element analysis software NASTRAN. It is shown that the spindle overhanging, bearing span have a significant effort on spindle deflection. The dynamic analysis shows no resonance will happen during its speed range. The methods and solutions for the motorized spindle system design and engineering applications was given in this paper.

Grinding is widely used as a precision process for machining difficult-to-cut materials. Grinding productivity is still greatly dependent on the experience and skill of human operators. Focusing on the indirect method, an attempt was made to build up an intelligent system to monitor the condition of grinding wheels with force signals and the acoustic emission (AE) signals. An artificial immune algorithm based multi-signals processing method was presented in this paper. The intelligent system is capable of incremental supervised learning of grinding conditions and quickly pattern recognition, and can continually improve the monitoring precision. The experiment indicates that the accuracy of condition identification is about 87%, and able to meet the industrial need on the whole.

Grinding is one of the most important operations in material processing. The study on grinding mechanism is difficult to carry out because of the difficulty in measuring the actual grinding temperature, stress and strain by experiments. Finite element analysis software Deform-3D is employed to create the Johnson-Cook material constitutive model for high-speed grinding simulation. Grinding model was constructed to reflect the temperature, strain and strain rate in the process of grinding 40Cr steel. The temperature of grinding area in simulation is analyzed to verify whether the finite element model is reasonable.

Due to the difficulty in arrangement of thermocouples, temperature measurement in grinding presents a number of challenges, particularly in high speed cylindrical-plunge grinding. Based on existing literature, only single thermocouple is considered for measuring the maximum temperature in the grinding contact arc, without considering the overall temperature variation. In this paper, a new method for temperature measurement, named four K-type thermocouples, is proposed aslant along the direction of the width of workpiece which is developed for measuring the overall contact arc in high speed cylindrical-plunge grinding. It is shown that the temperature increases to the maximum with a sharp gradient, then decreases due to the strengthening of cooling effect and the decrease of depth of cut, which is consistent with previous study. The measured temperature signal reveals the generation rule and dissipation rule of grinding heat.