Thermodynamic Mechanism of MQL Grinding with Nano Bio-lubricant

This book discusses the thermodynamic mechanism of MQL grinding with nano-biological lubricant from the force, heat, surface integrity, and micro-morphology. It makes up the fatal defect of the lack of heat transfer capability of traditional MQL grinding. The machining accuracy, surface quality, especially surface integrity of the workpiece, are significantly improved; at the same time, the service life of the grinding wheel is increased and the working environment is improved. The general scope of the book’s content is the effects of MQL grinding with nano-bio-lubricant on grinding force, thermal mechanism, and surface. It provides a new method of sustainable green grinding for environment-friendly, resource-saving, and energy-efficient utilization and solves the technical bottleneck of the insufficient capacity in MQL heat transfer. Preface Contents List of Figures List of Tables 1 Introduction 1.1 Introduction 1.1.1 Flooding Grinding 1.1.2 Dry Grinding 1.1.3 Cryogenic Cooling Grinding 1.1.4 MQL Grinding 1.1.5 Nanofluids MQL Grinding 1.1.6 Thermodynamic Action Laws in NMQL Grinding 1.1.7 Measurement Methods of Thermal Parameters in NMQL Grinding 1.2 Research Significance 1.3 Research Status in Thermodynamic Action Laws During Grinding 1.3.1 Research Status in China 1.3.2 Research Status in Foreign Countries 1.4 Research Status on Theoretical Modelling of NMQL Grinding Force 1.4.1 Kinematics of a Single Grain and Material Removal Mechanism 1.4.2 Mechanical Model of a Single Grain 1.4.3 Geometry and Kinematical Modelling of Ordinary Grinding Wheel 1.5 Research Status on Theoretical Modelling of NMQL Grinding Heats 1.5.1 Definition of Grinding Temperature Field 1.5.2 Solving Method of Grinding Temperature Field 1.5.3 Heat Source Distribution Model 1.5.4 Thermal Partition Coefficient Model in the Grinding Zone 1.6 Description and Explanation of Research Problems References 2 Analysis of Grinding Mechanics and Improved Predictive Force Model Based on Material-Removal and Plastic-Stacking Mechanisms 2.1 Introduction 2.2 Grinding Force Model of a Single Grain 2.2.1 Grains/Workpiece Interference Mechanism and Debris Thickness 2.2.2 Cutting Force Models 2.2.3 Ploughing Force Models 2.2.4 Frictional Force Models 2.3 Ordinary Grinding Wheel Models and Dynamic Active Grains 2.3.1 Protrusion Height of Grains in the Grinding Zone 2.3.2 Static Active Grains 2.3.3 Dynamic Active Grains and Cutting Depth 2.4 Grinding Force Models of Ordinary Grinding Wheel and Prediction 2.4.1 Construction of Grinding Force Models 2.4.2 Prediction of Grinding Force 2.5 Experimental Verification of Grinding Forces 2.5.1 Experimental Setup 2.5.2 Comparative Analysis Between Predicted Values and Test Results 2.5.3 Variation Trend Analysis of Grinding Force 2.6 Summary References 3 Velocity Effect and Material Removal Mechanical Behaviors Under Different Lubricating Conditions 3.1 Introduction 3.2 Material Removal Mechanical Behaviors of High-Speed Grinding Under Different Lubricating Conditions 3.2.1 Grain-Workpiece Interference Geometric Model 3.2.2 Mechanical Action Mechanism and Material Strain Rate in the Cutting Zone 3.2.3 Debris and Furrow Forming Mechanisms 3.3 Experimental Method of Single-Grain High-Speed Grinding 3.3.1 Building of the Experimental Platform 3.3.2 Discussion of Previous Single-Grain Experimental Methods 3.3.3 Experimental Methods of Single-Grain High-Speed Grinding Under Different Lubricating Conditions 3.4 Experimental Results and Discussions 3.4.1 Debris Morphology and Material Removal Mechanism 3.4.2 Plastic-Stacking Phenomenon and Influencing Factors 3.4.3 Effects of Lubricating Conditions and “Velocity Effect” on Unit Grinding Force 3.5 Summary References 4 Probability Density Distribution of Size and Convective Heat Transfer Mechanism of Nanofluid Droplets 4.1 Introduction 4.2 Research Status on Convective Heat Transfer Mechanism of Nanofluids Spray Cooling 4.2.1 Research Status of Heat Transfer Mechanism of Nanofluids in the Grinding Zone 4.2.2 Research Status of Convective Heat Transfer Coefficient in Spray Cooling 4.3 Mathematical Model of Convective Heat Transfer Coefficient Under Nanofluids Spray Cooling 4.3.1 Nanofluids Atomization Mechanism and Probability Density Distribution of Droplet Size 4.3.2 Effects of Airflow Field Around Micro-abrasive Tool on Droplet Distribution Pattern 4.3.3 Theoretical Models of Spray Boundary 4.3.4 Probability Density Statistics of Size of Droplets with Effective Heat Transfer 4.3.5 Convective Heat Transfer Coefficient Model of Nanofluids Spray Cooling 4.4 Conclusions References 5 Design and Experimental Evaluation of Convective Heat Transfer Coefficient Test System in Nanofluids Spray Cooling 5.1 Introduction 5.2 Research Status on Measuring Device of Convective Heat Transfer Coefficient 5.2.1 In-Pipe Transient Measurement of Convective Heat Transfer Coefficient 5.2.2 Measurement of Forced Convective Heat Transfer in a Narrow Annular Channel 5.2.3 Measurement of Convective Heat Transfer in Helical Grooved Tube with Inner Helical Teeth 5.3 Characterization of Thermophysical Properties of Nanofluids 5.3.1 Preparation of Medical Nanofluids 5.3.2 Characterization of Thermophysical Properties of Nanofluids 5.4 Design and Building of the Measurement System for Convective Heat Transfer Coefficient Under Nanofluids Spray Cooling 5.4.1 Experimental Principle 5.4.2 Design and Building of the Measurement System 5.4.3 Measuring Errors of Experimental Device 5.5 Experimental Result Analysis and Discussions 5.5.1 Experimental Results 5.5.2 Analysis and Discussions 5.6 Summary References 6 Research on Microscale Skull Grinding Temperature Field Under Different Cooling Conditions 6.1 Introduction 6.2 Definition of Grinding Temperature Field 6.3 Solving Method of Grinding Temperature Field 6.3.1 Solving Grinding Temperature Field Based on Analytical Method 6.3.2 Solving Grinding Temperature Field Based on Finite Difference Method 6.4 Boundary Conditions 6.4.1 Type-I Boundary Conditions 6.4.2 Type-II Boundary Conditions 6.4.3 Type-III Boundary Conditions 6.5 Constant Heat Source Distribution Model in Grinding of Metal Materials with Ordinary Wheel 6.5.1 Rectangular Heat Source Distribution Model 6.5.2 Triangular Heat Source Distribution Model 6.5.3 Parabolic Heat Source Distribution Model 6.5.4 Comprehensive Heat Source Distribution Model 6.6 Dynamic Heat Flux Model of Ductility Domain Removal of Hard and Brittle Bio-Bone Materials 6.6.1 Statistics on Effective Grinding Abrasive Number of Spherical Head 6.6.2 Energy Consumption for Plastic Shear Removal of Bone Material 6.6.3 Energy Consumption for Removal of Bone Material Powder 6.6.4 Dynamic Heat Flux Model for Ductility Domain Removal of Hard and Brittle Bio-Bone 6.7 Thermal Partition Coefficient Model in the Grinding Zone 6.7.1 Rated Heat Supply Coefficient Model at Grinding Points 6.7.2 Thermal Partition Coefficient Model of Grinding Wheel 6.7.3 Thermal Partition Coefficient Model of Abrasive/Grinding Fluid Complex 6.7.4 Thermal Partition Coefficient Model of Grinding Wheel/Workpiece System 6.7.5 Thermal Partition Coefficient Model Considering Convective Heat Transfer of Grinding Zone 6.8 Thermal Damage Domain in Dry Grinding of Bio-Bone 6.9 Summary References 7 Process Parameter Optimization and Experimental Evaluation for Nanofluid MQL in Grinding Ti-6Al-4V Based on Grey Relation Analysis 7.1 Introduction 7.2 Experimental Design 7.2.1 Experimental Equipments 7.2.2 Experimental Materials 7.2.3 Experimental Schemes 7.3 Results and Discussion 7.3.1 Single-Index SNR Analysis 7.3.2 Multi-Index Grey Correlation Analysis 7.4 Verification Experiment 7.4.1 Workpiece Surface Quality Analysis 7.4.2 Grinding Efficiency Analysis of Workpiece Material 7.5 Summary References 8 Temperature Field Model and Experimental Verification on Cryogenic Air Nanofluid Minimum Quantity Lubrication Grinding 8.1 Introduction 8.2 Numerical Simulation of Grinding Temperature Field 8.2.1 Mathematical Model of Grinding Temperature Field 8.2.2 Determination of Simulation Parameters 8.2.3 Numerical Simulation Results 8.3 Experimental Verification 8.3.1 Experimental Equipments 8.3.2 Experimental Materials 8.3.3 Experimental Design 8.3.4 Experimental Results 8.3.5 Comparison of Simulation and Experimental Results 8.4 Experimental Results Analysis and Discussion 8.4.1 Specific Grinding Force 8.4.2 Cooling Performance Evaluation Under Different Working Conditions 8.4.3 Boiling Heat Transfer Analysis 8.4.4 Effects of Workpiece and Debris Surface Characteristics on Cooling Heat Transfer 8.5 Summary References 9 Convective Heat Transfer Coefficient Model Under Nanofluid Minimum Quantity Lubrication Coupled with Cryogenic Air Grinding Ti-6Al-4V 9.1 Introduction 9.2 Experimental Design 9.2.1 Experimental Equipments 9.2.2 Experimental Materials 9.2.3 Experimental Schemes 9.3 Experimental Results 9.3.1 Specific Grinding Energy 9.3.2 Friction Coefficient 9.4 Experimental Results Analysis and Discussion 9.4.1 Lubrication Performance Evaluation Under Different Working Conditions 9.4.2 Effects of Temperature on Lubrication Performances 9.4.3 Atomizing Angle Analysis 9.4.4 Surface Roughness and Surface Morphology 9.5 Summary References 10 Effects of Cold Air Fraction in Vortex Tube on Heat Transfer Mechanism in CNMQL Grinding 10.1 Introduction 10.2 Numerical Simulation of Grinding Temperature Field 10.2.1 Mathematical Model of Grinding Temperature Field 10.2.2 Determination of Simulation Parameters 10.3 Numerical Simulation Results 10.4 Experimental Verification 10.4.1 Experimental Equipments 10.4.2 Experimental Materials 10.4.3 Experimental Design 10.4.4 Comparison of Simulation and Experimental Results 10.5 Experimental Results and Analysis 10.5.1 Specific Grinding Energy 10.5.2 Effects of Nanofluid Viscosity on Heat Transfer Performances 10.5.3 Effects of Surface Tension of Nanofluids on Heat Transfer Performances 10.5.4 Effects of Atomizing Effect and Boiling Heat Transfer on Heat Transfer Performances 10.6 Summary References 11 Effects of Nanofluid Concentration on Heat Transfer Performances in Cryogenic Nanofluid Minimum Quantity Lubrication Grinding 11.1 Introduction 11.2 Experimental Design 11.2.1 Experimental Equipments 11.2.2 Experimental Materials 11.2.3 Experimental Schemes 11.3 Experimental Results and Discussion 11.3.1 Grinding Temperature 11.3.2 Specific Grinding Energy 11.3.3 Effects of Viscosity and Contact Angle of Nanofluids on Heat Transfer Performances 11.3.4 Effects of Nanoparticle Dispersibility on Heat Transfer Performances 11.4 Summary References 12 Performances of Al2O3/SiC Hybrid Nanofluids in Minimum-Quantity Lubrication Grinding 12.1 Introduction 12.2 MQL Mechanism of Mixed Nanofluids 12.2.1 Thermophysical Properties of Al2O3 and SiC Nanoparticles 12.2.2 MQL Mechanism of Base Oil 12.2.3 Lubrication Mechanism of Mixed Nanoparticles 12.3 Performance Evaluation Parameters of Mixed NMQL 12.3.1 Grinding Force 12.3.2 Micro-friction Coefficient 12.3.3 Specific Grinding Energy 12.3.4 Removal Parameters of Workpiece 12.3.5 Workpiece Surface Quality 12.4 Research on Grinding Surface Homogeneity 12.4.1 Autocorrelation Analysis of Workpiece Surface Profile 12.4.2 Cross Correlation Analysis of Workpiece Surface Profile 12.4.3 Power Spectral Density Analysis of Workpiece Surface Profile 12.5 Summary References 13 Grinding Performances of Al2O3/SiC Mixed Nanofluid MQL with Different Mixratio 13.1 Introduction 13.2 Experimental Design 13.2.1 Experimental Setup 13.2.2 Experimental Materials 13.2.3 Experimental Conditions 13.2.4 Experimental Schemes 13.3 Experimental Results and Analysis 13.3.1 Grinding Force Ratio 13.3.2 Specific Grinding Energy 13.3.3 Surface Roughness of Workpiece 13.4 Discussion of Experimental Results 13.4.1 Lubrication Mechanism of Pure Al2O3 Nanofluid and Pure SiC Nanofluid 13.4.2 “Physical Synergistic Effect” Analysis of Al2O3/SiC Mixed Nanoparticles 13.4.3 Workpiece Surface Morphology and Profile Supporting Length Rate Curve 13.5 Summary References 14 Lubricating Property of MQL Grinding of Al2O3/SiC Mixed Nanofluid with Different Particle Sizes and Microtopography Analysis by Cross-correlation 14.1 Introduction 14.2 Experimental Design 14.2.1 Experimental Equipments 14.2.2 Experimental Materials 14.2.3 Experimental Schemes 14.3 Experimental Results 14.3.1 Specific Grinding Force 14.3.2 Removal Parameters of Workpiece 14.3.3 Surface Roughness of Workpiece 14.4 Analysis and Discussion 14.4.1 Lubrication Mechanism of Al2O3/SiC Mixed Nanofluids with Different Physical Encapsulation Effects 14.4.2 Effects of Contact Angle Between NMQL Droplet and Workpiece Surface on Lubrication Performances 14.4.3 SEM Analysis of Grinding Debris 14.4.4 Cross Correlation Analysis of Al2O3/SiC Mixed NMQL Under Different Size Ratios 14.4.5 Cross Correlation Analysis of Profile Curves at Two Points of the Same Workpiece Surface 14.5 Summary References 15 Spraying Parameter Optimization and Microtopography Evaluation in Nanofluid Minimum Quantity Lubrication Grinding 15.1 Introduction 15.2 Experimental Design 15.2.1 Experimental Equipments 15.2.2 Experimental Materials 15.2.3 Experimental Schemes 15.3 Experimental Results 15.3.1 SNR Analysis 15.3.2 Analysis of Variance 15.3.3 Optimization Results 15.4 Experimental Verification and Discussion 15.4.1 Power Spectral Density Analysis of Surface Profile 15.4.2 Surface Morphology of Workpiece and EDS 15.4.3 Debris Morphology and EDS 15.5 Summary References