Papers by Author: Cong Mao

Abstract: The grinding forces and grinding temperature were measured by using a 3-axis piezoelectric dynamometer and a thermocouple, respectively. The morphology and roughness of the ground surface were analyzed by using a scanning electron microscope (SEM) and a talysurf. It is found that the grinding parameters have great influence on the grinding temperature. Meanwhile, the down grinding has higher temperature than the up grinding. The relation among the grinding temperature, the morphology and the roughness of ground surface was discussed. It is found that when the grinding temperature is not high enough for the ground surface to appear obvious burn, the grinding temperature has little influence on the surface roughness.

Abstract: The properties of the white layer in the surface grinding are described. The influences of heat treatment, carbon content and grinding conditions on the white layer formation are discussed. It is found that the white layer in the hardened steel is thicker and harder than that in the annealed steel, and there is not a softer transition zone in the annealed steel. Higher carbon content tends to increase white layer thickness at the larger cutting depth, while no difference is observed at the smaller cutting depth. Increased carbon content tends to increase white layer hardness. The white layer thickness increases as the cutting depth increases. The white layer thickness increases with the rise of the table speed until a certain critical speed value is reached, beyond which the white layer thickness decreases with the increase of the table speed. The white layer in the central zone of the workpiece is thicker than that in the entrance zone, but it is thinner than that in the exit zone.

Abstract: In order to understand the grinding mechanism and analyze the grinding operation, it is necessary to study the contact phenomena between wheel and workpiece during grinding operation. The contact length, the grinding temperature distribution within the contact zone, and the grinding forces are measured in-process by using Critical Contact State mode, thermocouple method, and 3-axis piezoelectric dynamometer, respectively. It is found that the grinding conditions and the properties of work material have effects on the contact length, moreover, the mechanism of which is discussed in this paper. The results show that the contact length significantly interacts with grinding force and grinding temperature in the grinding zone.