Papers by Author: Y. Zhang

Abstract: The machinability of nickel-based superalloy GH4169 is very poor, the traditional machining of GH4169 using the cutting fluids with the active additives causes environmental and health problems, which is out of the request of the sustainable development strategy. In this paper a new green cutting technology with overheated water vapor as coolants and lubricants was proposed to achieve the aim of green cutting and high productivity. Cutting experiments and tool wear tests using carbide tool YG6 under dry cutting, emulsion and water vapor were performed. The cutting force, cutting temperature, machined surface quality and tool life were investigated; the curve of flank tool wear and relation between tool life and cutting velocity was carried out. The results of experiments indicated that during water vapor condition, the cutting force and cutting temperature was reduced, the machined surface roughness was improved, and the tool life was longed, respectively, and the higher velocity was taken during the some tool wear condition compared to dry cutting. The research results show that green cutting was achieved associated with overheated water vapor cooling and lubricating, at he same time the machined surface quality and production efficiency was increased.

Abstract: Green cutting has become focus of attention in ecological and environmental protection. Water vapor is cheap, pollution-free and eco-friendly. Therefore water vapor is a good and economical coolant and lubricant. Water vapor generator and vapor feeding system are developed to generate and feed water vapor. The lubricating method of water vapor is that the water vapor jet flow is directly jetted on the cutting zone and it cancels the fluid phase penetrating the capillaries in cutting zone. So it increases the time reserve of penetration and improves the property of penetration and lubricating effect. In order to find the influenced disciplinarians on lubricating effect with nozzle diameter, the parameters of water vapor jet flow and cooling distance (the distance between nozzle and cutting zone), experiments are carried out which hard alloy YT15 (P10 type in ISO) tool is used in cutting C45 steel. Experimental results show that the cutting force becomes lowered and chip thickness becomes thinned with the nozzle diameter decreasing. With the saturated vapor pressure increasing and the cooling distance shortening, the cutting force is lowed and the chip thickness is thinned too. Therefore the application of water vapor as coolant and lubricant can realize the green cutting in industry.