本文以車削和磨削過(guò)程的穩(wěn)定性為主要研究?jī)?nèi)容,基于對(duì)國(guó)內(nèi)外車削與磨削穩(wěn)定性研究現(xiàn)狀的分析,旨在通過(guò)刀具與工件系統(tǒng)的動(dòng)力學(xué)建模、仿真和實(shí)驗(yàn)的研究,深入揭示導(dǎo)致切削系統(tǒng)失穩(wěn)的內(nèi)在機(jī)理和主要原因,為進(jìn)一步提升工件的加工質(zhì)量和制造裝備的穩(wěn)定性提供理論參考。本文主要研究?jī)?nèi)容和結(jié)果包括:（1）提出了一種新的基于車削刀具偏轉(zhuǎn)引起的再生振動(dòng)模型,該模型將切削力作為影響刀具變形的主要因素,研究發(fā)現(xiàn),由于刀具與工件之間相互的非線性作用,刀具偏轉(zhuǎn)導(dǎo)致系統(tǒng)的復(fù)雜動(dòng)力學(xué)行為,從而導(dǎo)致顫振。系統(tǒng)呈現(xiàn)周期、準(zhǔn)周期和混沌運(yùn)動(dòng);同時(shí)進(jìn)給量和切削深度的增加會(huì)降低加工穩(wěn)定性;（2）采用三維有限元法分析計(jì)算了車刀在切削載荷作用下的撓度變化,及其對(duì)車削系統(tǒng)穩(wěn)定性的影響。實(shí)驗(yàn)結(jié)果表明,當(dāng)切削參數(shù)較小時(shí),切削系統(tǒng)處于穩(wěn)定工作狀態(tài);而當(dāng)車削速度和車削深度分別大于0.1mm/n和1.5mm時(shí),系統(tǒng)失穩(wěn)且顫振頻率逐漸增大,并在周期、準(zhǔn)周期和混沌狀態(tài)之間的躍遷;（3）建立了以工件為剛性、砂輪非線性二自由度質(zhì)量彈簧-阻尼振子的磨削加工的動(dòng)力學(xué)模型。對(duì)磨削力的法向分量和切向分量對(duì)平面磨削過(guò)程的影響研究,發(fā)現(xiàn)切削深度和切削速度的變化會(huì)引起了加工過(guò)... 

【文章來(lái)源】：蘭州理工大學(xué)甘肅省

【文章頁(yè)數(shù)】：184 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
Abstract
摘要
List of Symbols
Chapter 1 Introduction
    1.1 Motivation
    1.2 The scope of the research
    1.3 Research aim
    1.4 Research objective
    1.5 The layout of the dissertation
Chapter 2 Literature Review
    2.1 Overview
    2.2 Dynamics of the turning operation
        2.2.1 Cutting tools in turning operation
        2.2.3 Effects of the tool geometry on the dynamic stability of theturning operation
        2.2.4 Monitoring of the tool condition in the turning operation
        2.2.5 Vibrations in turning operation
        2.2.6 Chatter in turning operation
    2.3 Dynamics of the grinding operation
        2.3.1 Types of grinding operations
        2.3.2 Grinding wheel marking system
        2.3.3 Grinding forces
        2.3.4 Vibrations in grinding operations
        2.3.5 Dynamic stability in grinding operations
    2.4 Dynamic modeling in the machining processes
    2.5 Methods for chatter detection in machining processes
        2.5.1 Method of chip analysis
        2.5.2 Method of artificial intelligence
        2.5.3 Method of signal acquisition and processing
    2.6 Analytical methods for chatter detection in machining processes
        2.6.1 Method of Nyquist plots
        2.6.2 Method of Stability Lobe Diagram(SLD)
        2.6.3 Method of finite element analysis and finite element model(FEA/FEM)
Chapter 3 Experimental Equipment
    3.1 Introduction
    3.2 Basic equipment of the experimental setup
        3.2.1 Lathe machine
        3.2.2 High-speed steel cutting tool
        3.2.3 Flat surface grinding machine
        3.2.4 Cylindrical grinding machine
        3.2.5 Grinding wheel
        3.2.6 Force measurement dynamometer
        3.2.7 Charge amplifier
        3.2.8 Oscilloscope
        3.2.9 Data acquisition system(DAQ)
    3.3 Chapter summary
Chapter 4 Methods of Chatter Analysis in Machining Operations
    4.1 Introduction
    4.2 Methods of numerical integration in chatter analysis
    4.3 Time-domain analysis
    4.4 Frequency response analysis
    4.5 Finite Element Method(FEM)/Finite Element Analysis(FEA)
    4.6 Experimental methods in chatter analysis
    4.7 Chapter Summary
Chapter 5 Stability Analysis of the Turning Operation
    5.1 Introduction
    5.2 Development of mathematical formulation of a cantilever beam
    5.3 Estimation of the tool deflection by a simple cantilever beam model
    5.4 Dynamic cutting forces components with regenerative chatter inturning operation
    5.5 Dynamic cutting force model by the flexible cutting tool
    5.6 Dynamic model of the turning operation for cutting tool deflection
    5.7 Governing equation of the dynamic model vibration
    5.8 3-D Finite element model analysis
    5.9 Experimentation
    5.10 Experiment setup
    5.11 Results of model simulation for stability analysis of the turningoperation
        5.11.1 Cutting parameters
        5.11.2 Analysis of dynamic model vibration results
    5.12 3D-finite element model analysis results
    5.13 Experimental results
    5.14 Chapter Summary
Chapter 6 Stability Analysis of the Flat Surface Grinding Operation
    6.1 Introduction
    6.2 Modeling of vibration excitation forces in flat surface grindingoperation
    6.3 Vibration modeling of the flat surface grinding operation
    6.4 Experimental procedure
    6.5 Experimental setup
    6.6 Results analysis and discussion
        6.6.1 Vibration condition analysis of the flat surface grindingoperation
        6.6.2 Experimental verification
    6.7 Chapter summary
Chapter 7 Stability Analysis of the Traverse Cylindrical GrindingOperation
    7.1 Introduction
    7.2 Problem description
    7.3 Traverse cylindrical grinding process nonlinear dynamic modeling
        7.3.1 Workpiece nonlinear dynamics analysis
        7.3.2 Grinding wheel nonlinear dynamics analysis
    7.4 Experimental setup
    7.5 Results analysis and discussion
        7.5.1 Model simulation results
        7.5.2 Experimental results
    7.6 Chapter summary
Conclusions and Future Works
References
Publications Originated from this Dissertation
Acknowledgements
Appendix- Derivation of the equation to calculate the magnitude of thedeflection for a cantilever beam



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