Research On The Influence Of Cutting Parameters On Tool Wear And Surface Quality Under The MQCL Conditions And Evaluation Of Green Machining

In order to achieve green and sustainable manufacturing,energy-saving and emission-reduction are one of the current issues of manufacturing industry.Reducing the discharge of cutting fluid or without discharge is of great significance to the realization of green production in manufacturing industry.In recent years,the minimum quantity lubrication(MQL)has been widely concerned.A sea of research results show that the technology can maintain the same machining quality and tool life as the traditional casting machining under specific conditions,but there is a disadvantage of insufficient cooling in the cutting area.In order to further improve the processing performance of MQL,researchers put forward the technology of minimum quantity cooling lubrication(MQCL).A large of studies show that MQCL can greatly extend the tool life and reduce the surface roughness.However,there is a gap in the research of the influence trend and mechanism of cutting parameters on tool wear and surface quality under MQCL conditions.This paper received the support from the key research and development project of Sichuan Provincial Science and Technology Department(2019YF0385).In this work,plant-based green lubricating oil is used as cutting fluid.With the low-speed and high-speed cutting under MQCL condition,the influence and mechanism of cutting parameters on tool wear and surface quality are studied,and the cutting parameters and processing methods are optimized.The main contents of this paper are as follows:(1)Based on the experimental results,the relationship between cutting parameters,tool wear and tool vibration were studied.The response surface of cutting parameters to tool wear under MQCL condition was established,and the interaction of cutting parameters was analyzed.According to the micro morphology of tool wear observed by SEM,the mechanism of tool wear was analyzed in the low-speed and high-speed cutting.The element composition of the wear area of the back face is analyzed by EDS,and the wear mechanism of the tool under MQCL condition is further revealed.The results show that cutting speed is the most important factor of tool wear and vibration,and the main reason of tool vibration is the increase of tool wear.The combination of cutting speed and feed will increase the tool wear rate,and the combination of cutting depth and feed has few effects on tool wear.The main causes of tool wear in low speed cutting are adhesive wear and abrasive wear.In high speed cutting,diffusion wear and oxidation wear are the main causes.(2)The response surface and variance analysis model of the influence of cutting parameters on surface roughness were established,and the trend of the influence of cutting parameters on surface roughness was analyzed.The surface quality profile parameters of MQCL and dry machining were analyzed and compared.The surface morphology and non-parametric description of the machined surface are evaluated,and the mechanism of surface wear under the two machining modes was analyzed.The results show that the feed rate has the most significant effect on the surface roughness,while the change of cutting depth has few effects on the surface roughness.Low speed and low feed cutting parameters are favorable for dry cutting.However,With the increase of feed rate and cutting speed,the peak and valley of the surface contour gradually increase,and MQCL machining mode is more conducive to obtain a smoother surface.Furthermore,the surface under MQCL conditions has a smoother support rate curve and a concentrated material ratio distribution,which shows that the machined surface has better compression resistance and wear resistance.(3)The prediction model and parameter optimization model of tool wear under MQCL were established and verified by experiments.The optimization model of hybrid machining mode was established,and its machining performance was verified by experiments.The evaluation system of green cutting sustainability was established,and the cutting parameters and influencing factors were evaluated.The results show that the accuracy of the model is 96.45% and 94.15% respectively.The experimental results show that the error rate is 2.15% and 6.48%,indicating that the model and optimization method are reliable.Furthermore,the verification experiments show that the tool wear and surface roughness obtained by MQCL are lower than those of MQL and dry cutting.The experimental results show that the surface quality is similar to MQCL,but the cutting fluid and energy consumption are lower than MQCL.The results of green cutting sustainability assessment show that the cutting parameters keep the greatest influence on tool wear and indicated quality in dry cutting.The hybrid machining is the most suitable strategy for green cutting,followed by MQL.