| In traditional metal cutting processing,in order to ensure the accuracy and processing efficiency of the parts,the auxiliary processing is through the use of cutting fluid.However,after the cutting fluid is poured on the surface of the workpiece,a part of it will drift to the surrounding environment,and the operator will inhale the mist of the cutting fluid in the air,which will cause respiratory diseases and skin diseases.In order to realize the green manufacturing of the cutting process,the degradable bio-lubricant minimum quantity lubrication technology came into being.Furthermore,adding nanoreinforced phase can effectively improve the anti-wear and anti-friction properties of the liquid lubricating medium.However,the mechanical behavior of material removal and the mechanism of surface creation under the above lubrication conditions were still unclear;at the same time,it’s still difficult to accurately and controllably transport the lubricating medium to the cutting area under continuous cutting and boundary conditions of high temperature,pressure and high shear rate.Based on the above problems,this paper carried out the research on the mechanism of nano-enhanced bio-lubricant minimum quantity lubrication turning processing material removal and micro-channel auxiliary lubrication synergistic mechanism.The mechanical behavior of material removal in the cylindrical turning process was studied,and the influence of lubrication methods and cutting parameters on the cutting force was revealed.The theoretical model of the surface topography of the cylindrical turning workpiece was studied,and the relationship between the residual height of the workpiece surface and the cutting parameters was revealed.The mechanism of microchannel assisted lubrication synergies is studied,and the influence of texture arrangement direction on nanofluid minimum quantity lubrication is revealed.Details are as follows:1.The problems and technical bottlenecks in traditional cutting have been analyzed.The development status of sustainable cutting technology was analyzed.Furthermore,the relevant research teams and academic progress of cutting fluid reduction supply and cutting technology at home and abroad were analyzed.Finally,the research content and technical route of this article were determined.2.The performance of nano-enhanced bio-lubricant in minimum quantity lubrication turning was analyzed.And from the perspective of lubrication mechanism,it was revealed the influence mechanism of degradable vegetable oil,nano-reinforced phase and proportioning concentration on cutting performance.The law of atomization method,physical and chemical properties of vegetable oil(wettability,fatty acid,stability),nanoreinforced phase(material,particle size,shape,mixed particles)and ratio of concentration on the anti-wear and anti-friction effect of lubricating medium have been analyzed.3.The cutting force prediction model for external turning material removal was established.The influence of different lubrication methods on tool/chip interface friction,constitutive parameters and cutting parameters on cutting force was analyzed and verified by experiments.The influence mechanism of lubrication method,cutting depth and tool feed rate on cutting force during material removal was revealed.4.The creation mechanism of the surface morphology of external turning was studied.The influence of tool nose arc radius and feed on the residual height of the workpiece surface was analyzed.The three-dimensional surface topography prediction model of the workpiece under the influence of tool geometric parameters,cutting parameters,material elastic recovery and plastic lateral flow was established and carried out experimental verification.5.A numerical simulation model of the wetting characteristics of the lubricating medium with the aid of micro-channels is established.The spread and infiltration state of micro-droplets on the surface of conventional cutting tools and micro-grooves was studied.The transient evolution law of lubricating medium spreading on the auxiliary interface of microchannel was revealed.A comparative experiment on the external cutting performance of different layout texture tools under nano-enhanced bio-lubricant was carried out.The influence of the microstructure arrangement direction of the tool rake face on the cutting force and surface micro-topography(workpiece,tool and chip)was revealed. |
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