Study Performance Of Cylindrical Grinding On Surface Roughness.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

Study Performance of Cylindrical Grinding

on Surface Roughness

Thesis submitted in accordance with the requirements of the Universiti Teknikal Malaysia Melaka for the Bachelor of Manufacturing Engineering

(Manufacturing Process)

Ahmad Anwar Bin Hamdan

(B050510078)

Faculty of Manufacturing Engineering May 2008

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UTeM Library (Pind.1/2007)

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PSM JUDUL:

Study Performance of Cylindrical Grinding on Surface Roughness

SESI PENGAJIAN:

Semester 2 2007/2008

Saya Ahmad Anwar Bin Hamdan

mengaku membenarkan laporan PSM / tesis (Sarjana/Doktor Falsafah) ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Laporan PSM / tesis adalah hak milik Universiti Teknikal Malaysia Melaka dan

penulis.

2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan

untuk tujuan pengajian sahaja dengan izin penulis.

3. Perpustakaan dibenarkan membuat salinan laporan PSM / tesis ini sebagai bahan

pertukaran antara institusi pengajian tinggi.

4. *Sila tandakan (√)

SULIT

TERHAD

TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia yang termaktub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

(TANDATANGAN PENULIS) Alamat Tetap:

Batu 8, Kg Paya Luas Batu Anam

85100 Segamat Johor Darul Takzim Tarikh: 20 MAY 2008

(TANDATANGAN PENYELIA) Cop Rasmi:

Tarikh: _______________________ * Jika laporan PSM ini SULIT atau TERHAD, sila lampirkan surat daripada pihak organisasi berkenaan

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DECLARATION

I hereby declare that this report entitled “Study Performance of Cylindrical Grinding on Surface Roughness” is the result of my own research except as cited in the

references.

Signature :

Author’s Name : Ahmad Anwar Bin Hamdan

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APPROVAL

This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a partial fulfillment of the requirements for the degree of Bachelor of Manufacturing

Engineering (Manufacturing Process). The members of the supervisory committee are as follow:

……….

(PSM Supervisor)

Mr. Mohamad Amri Bin Sulaiman (Official Stamp & Date)

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ABSTRACT

This research presents the effects of cylindrical grinding parameters (spindle speed, traverse speed, and depth of cut; infeed) on the surface roughness for PS A 80 K 8 V 6N grinding wheel tools, in grind AISI 1040 medium carbon steel. The process of grinding was done by Universal Cylindrical Grinder SHARP OD618 S/H with traverse grinding operation selected. The intervals of parameters were decided after referred from suitable recommendation provided. The surface roughness value will obtained by using Mitutoyo’s SJ-301 surface roughness tester. The result will compare with experiment hypothesis to measure the affect of variable parameter to surface roughness changes. Interpretation of result will used for further reference for checking suitable condition parameter on various conditions of operations.

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ABSTRAK

Penyelidikan ini merangkumi kesan parameter (spindle speed, traverse speed dan depth of cut) daripada operasi cylindrical grinding terhadap kekasaran permukaan dengan penggunaan pengisar batu canai PS A 80 K 8 V 6N pada bahan keluli karbon sederhana AISI 1040. Proses mengisar telah dilakukan oleh Universal Cylindrical Grinder SHARP OD618 S / H dengan kelajuan operasi mengisar yang telah ditetapkan. Selang bagi setiap parameter ditetapkan dengan merujuk aturan dan cadangan kelajuan bagi setiap parameter. Kemudian, nilai kekasaran permukaan akan memperolehi dengan menggunakan Mitutoyo's SJ-301; penguji kekasaran permukaan. Hasilnya akan bandingkan dengan hipotesis eksperimen mengukur kesan parameter serta pembolehubah untuk setiap perubahan kekasaran permukaan. Keputusan yang dicapai adalah berguna sebagai rujukan dalam memilih kesesuaian parameter di dalam pelbagai operation pencanaian.

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DEDICATION

For my beloved parent, my family best friend and all friends, and to those who’s with me all this time

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ACKNOWLEDGEMENTS

Alhamdulillah, thank to Allah the Almighty God for giving me strength and patience to work on this Final Year Project Report.

I would like to take this opportunity to express my sincere and deepest gratitude to my Project Supervisor; Mr. Mohamad Amri Bin Sulaiman, for his guidance and opinion in the cause of completing this report.

My greatest thanks to my beloved family for their prayers, support, and encouragement to me for throughout this entire period of these Final Year Project 1 and 2. I would like to thanks Professor Dr. Mohd. Razali Bin Muhamad; Dean of Faculty of Manufacturing Engineering, University Technical Malaysia, Melaka, Mr. Mohd Hadzley Bin Abu Bakar; Academic Supervisor, and to all the lectures in the faculty.

I also would like to convey my biggest thanks to all FKP technicians for supporting me throughout my project. The knowledge and experience I gained from you all will not be forgotten.

I’m also obliged to everyone who had directly and indirectly involve through

contributions of ideas, as well as materials and professional opinions.

Last but not least, to Yeoh Phooi San and. all my friends out there for their moral support and valuable help that they have provided me throughout my project.

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Abstract i

Dedication iii

Acknowledgements iv

Table of Contents v

List of Figures ix

List of Tables xii

List of Abbreviations, Symbols, Specialized Nomenclature xiii

List of Appendices xiv

1. INTRODUCTION 1.1 Background of Project 1

1.2 Objective 2

1.3 Scope of Project 2

2. LITERATURE REVIEW 2.1 Introduction 4

2.2 Review: Grinding Due to Surface Finish 5

2.2.1 Reasons for Grinding 7

2.2.2 Machining removes excessive material 8

2.3 Review: Cylindrical Grinding 9

2.3.1 Introduction 9

2.3.2 Cylindrical Grinding Machine 9

2.3.3 Concept in Cylindrical Grinding 10

2.3.4 Method in Cylindrical Operation 14

2.3.5 Grinding Wheel 15

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2.3.5.2 Abrasive Grain Properties 17 2.3.5.3 Standard Marking System Chart 18

2.4 Parameter in Grinding 20

2.5 Review: Surface Integrity 21

2.5.1 Introduction 21

2.5.2 Review: Surface Roughness 22

2.5.2.1 Description of Surface Roughness 24

2.5.3 Surface Roughness Measurement 26

2.5.3.1 Direct Measurement Methods 27

2.5.3.2 Comparison Based Techniques 27

2.5.3.3 Non Contact Methods 27

2.5.3.4 On-process measurement 28

2.6 Review: Profilometer 29

2.6.1 Advantages of contact profilometers 30

3. METHODOLOGY

3.1 Studies of Cylindrical Grinding Operation and Process 32

3.1.1 Traverse Grinding Operations 34

3.1.2 Grinding Wheel Specification 34

3.1.3 Wheel Marking 35

3.2 Research of Parameter in Cylindrical Grinding Process 35

3.2.1 Wheel Speed 35

3.2.2 Traverse Speed 37

3.2.3 Depth of Cut 39

3.2.4 Parameter Selected for Further Studies 39 3.3 Training with Universal Cylindrical Grinder 41

3.4 Planning for Material Preparation 44

3.5 Perform Grinding Operation on Parameters Selected 45

3.5.1 Starting up Machine 46

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3.5.2.1 Truing 48 3.5.2.2 Dressing 49 3.5.2.3 Truing and Dressing a Grinding Wheel 49 3.5.3 Performing Grinding on the Workpiece 52 3.6 Study and Applying Measurement Method for Surface Roughness 59 3.7 Recording, Collecting and Analyzing Data Measurement and Data

of Surface Roughness 62

4. RESULT

4.1 Introduction 63

4.2 Area of Contact 63

4.3 Effect of Grinding Due To Surface Roughness 64

5. DISCUSSION

5.1 Introduction 71

5.2 Influences in Grinding Operation 71

5.3 Influences in Method of Measurements 72

5.4 The Surface Finish Factors by Spindle Speed 72 5.5 The Surface Roughness Factors by Traverse Speed 74 5.6 The Surface Roughness Factor by Grinding Wheel Infeed (depth of cut) 76 5.7 Factor of Traverse Length of Wheel to Sample 77

5.8 Relations between Parameters 79

5.9 Factor from Process in Grinding Operation 84

5.9.1 Un-uniformity Dressing 84

5.9.2 Spark 85

5.9.3 Grinding Fluid 86

6. CONCLUSION

6.1 Conclusion 88

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REFERENCES 91

APPENDICES

A Wheel Marking & Shape of Wheel B Machine Specifications

C Description of Machine D Machine Features E Cutting Parameter

F Material Properties AISI 1040

G Standards Sj-301 Configuration H Switching the Profile Filter

I Evaluation According To JIS B0601-2001 and ISO J Table and Result of Measurement

K ISO 4288, 1996: Surface Roughness Texture: Profile Method – Rules and Procedures for the Assessment of Surface Texture

L The Indication of Surface Lay According To ISO 1302, 2001 M Roughness from Process Factor

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LIST OF FIGURES

Figure 2.1 The Input, Constraints, Outputs and Mechanism considered when analyzing and modelling a grinding process (Warren Richard, 1992).

Figure 2.2 Example of various cylindrical operation including traverse grinding, plunge grinding, and profile’s grinding (Kalpakjian S, 2001).

Figure 2.3 External and internal grinding for traverse and plunge process. (Prof. Dr.-Ing. F. Klocke, 2007).

Figure 2.4 Various grinding operation for cylindrical part (Geoffrey Boothroyd, 1989).

Figure 2.5 Traverse grinding operation with different traverse speed (Franklin D. Jones, 1964).

Figure 2.6 Condition for external grinding (Black S C, 1998). 15

Figure 2.7 Types of abrasive grain in wheels. 16

Figure 2.8 Composition of an abrasive wheel (S C Black 1998). 17 Figure 2.9 Friability of wheel during grinding operation (Warren Richard,

1992).

Figure 2.10 Hardness comparison between abrasive grain (Warren Richard, 1992).

Figure 2.11 Industry Standard of wheel specifications (Pacific Grinding Wheel Company).

Figure 2.12 Parameters have to control during grinding operation (Franklin D. Jones, 1964).

Figure 2.13 Profile in surface appeared on the workpiece (S C Black, 1998). 23 Figure 2.14 Checking profile on surface using stylus method

(http://en.wikipedia.org/wiki/Profilometer).

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2002).

Figure 2.16 Electronic speckle correlation using lens (A. W. Batchelor, 2002).

Figure 2.17 Schematic figure checking roughness using stylus method (http://en.wikipedia.org/wiki/Profilometer).

Figure 3.1 Universal Cylindrical Grinder (refer Appendix C). 34 Figure 3.2 Universal cylindrical grinder for external, internal and taper

grinding process.

Figure 3.3 Chuck for ground the cylindrical workpiece. 42

Figure 3.4 Wheel for external grinding process. 43

Figure 3.5 Wheel to control depth of cut and table traverse. 4.3

Figure 3.6 Control and switch panel. 44

Figure 3.7 Internal grinding process through bore in workpiece. 44 Figure 3.8 Raw material before processing to be sample. 45

Figure 3.9 Switch for power on. 46

Figure 3.10 The buttons pushed simultaneously. 47

Figure 3.11 Main switch at the machine has to switch on. 47 Figure 3.12 Power button on the control panel has to push ON. 48 Figure 3.13 End stock which attach with diamond dresser. 50 Figure 3.14 The diamond dresser move ahead close to the wheel. 50

Figure 3.15 Auto-traverse dressing. 51

Figure 3.16 Infeed for dressing the wheel with suggested amount. 52

Figure 3.17 Place the workpiece into the chuck. 53

Figure 3.18 Fasten the workpiece on chuck properly. 53

Figure 3.19 Coolant is flushing on the grinding wheel. 54

Figure 3.20 Slowly infeed the samples to the wheel. 55

Figure 3.21 Set up the correct spindle speed as parameter required. 55 Figure 3.22 Set up correct traverse speed as parameter required. 56 Figure 3.23 Set position of reversing dog for table traverse. 56

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Figure 3.33 Knob for locking the table for auto-traverse cycle. 57

Figure 3.34 Set the infeed to zero align. 57

Figure 3.35 Cycling the operation until meet the parameter. 58 Figure 3.36 Normal position should be set after machining done. 58

Figure 4.1 Point for taken measurement. 64

Figure 4.2 Interrelation of spindle speed effect to surface roughness. 66 Figure 4.3 Interrelation of traverse speed effect to surface roughness. 68 Figure 4.4 Interrelation of depth of cut (infeed) effect to surface roughness. 70

Figure 5.1 Slope of effect by spindle speed to surface roughness. 73 Figure 5.2 Small spark produced in 10.72 rpm of spindle speed. 74 Figure 5.3 Slope of effect by traverse speed to surface roughness. 75 Figure 5.4 Crossed lay produces in high traverse speed. 75 Figure 5.5 Slope of effect by depth of cut (infeed) to surface roughness. 77 Figure 5.6 Length of grounded and grinding area on sample. 78 Figure 5.7 Influencing of parameters to result the surface roughness. 79 Figure 5.8 Interrelation of spindle speed and traverse speed. 81 Figure 5.9 Interrelation of spindle speed and depth of cut (infeed). 82 Figure 5.10 Interrelation of traverse speed and depth of cut (infeed). 83 Figure 5.11 Roughness of wheel effect by dressing lead (David J.

Whitehouse).

Figure 5.12 Insufficient grinding fluid and viscous. 86

Figure 5.13 Grinding fluid mixed with metal dust. 87

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LIST OF TABLES

Table 3.1 Recommend wheel speed (Roger Timing, 2002). 36 Table 3.2 Workpiece periphery speed range (Asian Autotec, 2007). 37 Table 3.2 Feed rate per grinding (Asian Autotec, 2007). 38 Table 3.4 Relation between variable and fix parameters. 39 Table 3.5 Range of spindle speed with fix other parameters. 40 Table 3.6 Range of traverse speed with fix other parameters. 40 Table 3.7 Range of depth of cut with fix other parameters. 41

Table 4.1 Data Recorded of surface roughness measurement in spindle speed parameter.

Table 4.2 Data recorded of surface roughness measurement in traverse speed parameter.

Table 4.3 Data recorded of surface roughness measurement in depth of cut (infeed) parameter.

Table 5.1 Clashing points of Ra between spindle speed and traverse

speed.

Table 5.2 Clashing points of Ra between spindle speed and depth of cut

(infeed).

Table 5.3 Clashing point of Ra between traverse speed and depth of cut

(infeed).

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LIST OF ABBREVIATIONS, SYMBOLS, SPECIALIZED

NOMENCLATURE

HV Hardness Vickers

SEM Scanning Electron Microscope

Sk Skewness Of The Profile

AISI 1040 Medium Carbon Steel Graded By American Iron And Steel Institute

Ra Arithmetic Mean Deviation Of The Profile Rmax Maximum Peak To Valley Height Of The Profile

Rp Maximum Profile Height

Ry Maximum Height Of The Profile

μm Micrometer (Micron)

CCD Charge-Coupled Device

CLA Center Line Average

PS A 80K V 6N Wheel Grade: [PS; Manufactures Abrasive Code][A; Aluminum Oxide][80; Grain Size, Fine][K; Grade, Medium][V; Porosity][V; Bond Type, Vitrified][6N; Manufactures Bond Code]

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LIST OF APPENDICES

A Wheel Marking & Shape of Wheel B Machine Specifications

C Description of Machine D Machine Features E Cutting Parameter

F Material Properties AISI 1040

G Standards Sj-301 Configuration H Switching the Profile Filter

I Evaluation According To JIS B0601-2001 and ISO J Table and Result of Measurement

K ISO 4288, 1996: Surface Roughness Texture: Profile Method – Rules and Procedures for the Assessment of Surface Texture L The Indication of Surface Lay According To ISO 1302, 2001

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CHAPTER 1 INTRODUCTION

1.1 Background of Project

Cutting processes are among the most important of manufacturing operation. They are often necessary in order to impart the desired surface finish and dimensional accuracy to component, particularly those with complex shape that cannot be produced economically or properly by other techniques.

A large number of variables have significant influence on the mechanics of chip formation in cutting operations. Commonly observed chip types are continuous, built-up edge, discontinuous and segmented. Among important process variables are tool shape and material, cutting conditions such as speed, feed, and depth of cut, use of cutting fluids, and the characteristics of the machine tool, workholding device, fixturing, as well as the characteristics of the workpiece material, parameters influenced by these variables are force and power consumption, tool wear, surface finish and integrity, temperature, and dimensional accuracy of the workpiece. Machinability of materials depends not only on their intrinsic properties, but also on proper selection and control of process variables.

The distinction between a finishing operation and other processes that affect the surface is that finishing processes are not intended significantly change the dimension of a part (William O. Feller, 2001). Rather, this finishing operation is intended to achieve closer tolerances and provide protective coating. It is also able to improve the appearance of the part.

Surface finish is specified by giving the desired waviness, roughness, and lay of the desired surface. Waviness refers to the long-range undulations in the surface, not necessarily those left by the tool marks. Roughness refers to the finely spaced

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textured irregularities. Roughness is usually determined by the tool marks of the final operation.

The quality of machined surface is characterized by the accuracy of its manufacture with respect to the dimensions specified by the designer. Every machining operation leaves characteristic evidence on the machined surface. This evidence in the form of finely spaced micro irregularities left by the cutting tool. Each type of cutting tool leaves its own individual pattern which therefore can be identified. This pattern is known as surface finish or surface roughness.

1.2 Objective

The objectives of this experiment are:

(a) To study the relationship between the surfaces roughness values and cylindrical grinding parameters such as spindle speed, traverse speed and also depth of cut. From the study, we were able to study performance the cylindrical grinding due to its parameter to produces better surface finish.

(b) To analyzed the surface roughness of the material of cylindrical grinding operation such as the surface texture and surface profile.

1.3 Scope of Project

This project is about investigating the surface roughness on medium carbon steel AISI 1040 during cylindrical grinding operation using PS A 80 K 8 V 6N wheel as cutting tools. This process is done on the Universal Cylindrical Grinder OD-618 S/H in the room temperatures. During this machining several cutting parameters such as feed rate, spindle speed and depth of cut are frequent varied in selected range with 1960 rpm of grinding wheel are fixed. 45 samples are used to complete all parameters decided to further surface roughness analyzing.

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Profilometer of Surface roughness Tester Mitutoyo SJ-301, of will be used to measure and identify the surface roughness and it values. This will determine the surface roughness of the material after completing the grinding operations. The factors that influence the surface roughness is will be identified after the material have been machined.

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CHAPTER 2 LITERATURE REVIEW

2.1 Introduction

Machine tools and cutting tools have advanced in great developments in the past few years. In the past few years ago, machining is a difficult task to be performed but now this task has become common place and have been simplified with more advanced technology that have been involved. Machining, the broad term used to describe removal of material from a workpiece (Kalpakjian S, 2001).

Each process should be studied in order to understand the interrelationships of design parameters, such as dimensional accuracy, surface finish and integrity, and process parameters such as speed, feed, depth of cut, tool material and shape, and cutting fluids.

A variety of abrasive processes and machinery are available for surface, external, and internal grinding. The selection of abrasives and process variable in these operations must be controlled in order to obtain the desired surface and dimensional accuracy. Otherwise, damage to surfaces such as burning, heat checking, and harmful residual stresses may develop. Several finishing operations are available for debarring. Because contribute significantly to product cost, proper selection and implementation of finishing operations are important.

In written of William O. Feller (Fellers W. O., 2001), the result to breaking and cutting a piece of material depends on several factors:

(a) The properties of the material being cut. (b) The properties of the cutting tool. (c) The speed at which the material is cut.

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Those factor giving then the result on the workpiece such as geometric shape, dimension, appearance, and also surface integrity. Thus some parts that have been producing in machining would to have other finishing operations, such as grinding. This operation is important to obtain the desire final dimension and surface finish (Kalpakjian S, 2001).

The principle differences between the cutting action of grinding and other removal operation lie in the following (S C Black, 1998):

(a) Grinding grits are sufficiently hard to cut fully hardened steels of the order of 850 HV.

(b) The cutting angles of the grits have random geometry.

(d) The size of the chips cut is very small for grinding.

2.2 Review: Grinding Due to Surface Finish

When study of a geometry and surface finish of metal removing, is necessary in order to achieve efficiency of operations. When roughing, the aim is to remove a particular volume of metal in minimum time, when finishing, the area finished surface produced is the criterion, and where the area surface produced is the decisive feature.

Since the metal removal rate w = df x Vc mm3/s, any increase in cutting speed, depth of cut of feed will give a directly proportional increase in the metal removal rate. The power available at the machine spindle is one factor limiting the metal removal rate (Black S C, 1998).

Grinding and various abrasive-removal processes are capable of producing the finest accuracy and surface finish in manufactured products. The majority of abrasive processes are basically finishing operations that are usually performed on machined or cold-worked parts. However, abrasives are also used for large-scale

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material-removal processes, such as creep-feed grinding (http://industrialtech.freeservers.com).

As with other conventional grinding processes, cylindrical grinding is a manufacturing method using tools with lots of undefined geometrical cutting edges, which are formed by a large number of abrasive grains made of natural or synthetic abrasive material that remove the workpiece material at high speeds. In the case of external cylindrical grinding, two cylindrical bodies generally come into contact with each other. The length or surface of contact is relatively small (Tawakoli T. et al, 2006).

In the grinding process, because of the undefined geometrical cutting edges, there is a large amount of heat caused by different mechanism of shear, friction and separation, which is only partially dissipated by the chips and the rest can lead to a considerable thermal strain and burning on the workpiece and also on the tools. The reduction of heat build-up and proper cooling during grinding are therefore of immense importance (Tawakoli T. et al, 2006).

The geometrical parameters like tolerances or roughness are generally determined by the workpiece drawing and they are fixed. In order to achieve such geometrical parameters and defined accuracy, grinding parameters like depth of cut or traverse feed should be so selected in such a way that grinding forces do not exceed from a critical amount which causes thermal damage. It means that they must be relatively small. Unfortunately, these limited grinding forces decrease material removal rate and increase production time (Tawakoli T. et al, 2006).

Chatter is critical to grinding processes because accuracy and surface finish are the two major purposes for grinding processes. In addition, grinding processes are inherently susceptible to chatter. When chatter boundaries are known, one can design a grinding process without chatter. Thus, it is important to study chatter mechanisms and predict grinding chatter boundaries and growth rates (Hongqi Li et al, 2007).

Most recently, Li and Shin (Hongqi Li et al, 2007) presented a comprehensive time-domain dynamic model, which simulates cylindrical plunge grinding processes under general grinding conditions. The model focused on the prediction of grinding chatter boundaries. Critical issues were considered in the

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CHAPTER 1

INTRODUCTION