Surface Integrity Of AISI 1045 Steel When Machined With TiC Cutting Tool.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

SURFACE INTEGRITY OF AISI 1045 STEEL

WHEN MACHINED WITH CARBIDE-TiC

CUTTING TOOL

Thesis submitted in accordance with the requirements of the University Technical Malaysia Melaka for the Degree of Bachelor of Engineering (Honors) Manufacturing (Process)

Mohd Hilmy Bin Mohd Yusof

Faculty of Manufacturing Engineering Jun 2007

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APPROVAL

This thesis submitted to the senate of UTeM and has been accepted as partial fulfillment of the requirements for the degree of Bachelor of Manufacturing Engineering (Manufacturing Process). The members of the supervisory committee are as follow:

………. Main Supervisor

(Official Stamp & Date)

……… Co-Supervisor

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DECLARATION

I hereby, declare this thesis entitled “Surface Integrity of AISI 1045 Steel When Machined With Carbide-TiC Cutting Tool” is the results of my own research except as

cited in the reference.

Signature : ………

Author’s Name : MOHD HILMY BIN MOHD YUSOF

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ABSTRACT

This research presents the effects of turning cutting parameter (cutting time, speed and feed rate) on the surface integrity for TiC cutting tools in turning AISI 1045 medium carbon steel. Scanning Electron Microscope (SEM) is used to evaluate the surface integrity and the surface roughness value were obtained using Mitutoyo’s surface tester. The hard turning process is characterized by the generation of high temperature, high ratio of thrust tangential force component. The results shows that surface roughness and flank wear increased due to increased of the cutting time by fixing the cutting time, the cutting temperature can be controlled as the machining is subjected to the heat generate.

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DEDICATION

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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 Raja Izamshah b. Raja Abdullah , 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 throughout this entire period of this Final Year Project. 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 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 all my friends out there for their moral support and valuable help that they have provided me throughout my project.

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Page

Abstract i

Dedication ii

Acknowledgement iii

Table of Contents iv

List of Figures ix

List of Tables xii

Sign and Symbols xii

CHAPTER I INTRODUCTION 1

1.1Objectives 2

1.2Scope of project 3

CHAPTER II LITERATURE REVIEW 4

2.1 Introduction 4

2.2 Common Machine Tools 6

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2.3.1 The Basic Parts of Lathe Machine 8

2.3.2 Type Of Lathe 11

2.3.3 Computer Numerical Control (CNC) Lathes 12 2.3.4 Operations Performed In a Center Lathe 13

2.3.4.1 Boring 13

2.3.4.2 Facing 14

2.3.4.3 Threading 15

2.3.4.4 Drilling 15

2.3.4.5 Knurling 16

2.4 Cutting Tools In Turning 16

2.4.1 Type of metal cutting 17

2.4.2 Cutting Geometry 17

2.4.3 Cutting Tool Material 22

2.4.4 Requirements Of Tool Materials 22

2.4.5 Type Tool Materials 23

2.4.5.1 High-speed steel (HSS) 23

2.4.5.2 Cast Cobalt Alloys 24

2.4.5.3 Cemented Carbide 24

2.4.5.4 Diamond 24

2.4.5.5 Ceramics 25

2.4.5.6 Cubic Boron Nitride 25

2.4.6 Coating Materials of Cutting Tools 25

2.4.6.1 Titanium nitride (TiN) 26

2.4.6.2 Aluminum Oxide(Al2O3) 26

2.4.6.3 Titanium aluminum nitride (TiAlN) 26

2.4.7 Tool Coating Processes 27

2.4.7.1 Chemical vapor deposition (CVD) 27 2.4.7.2 Physical Vapor Deposition (PVD) 28

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2.5 Surface Integrity 28

2.5.1 Surface finish 31

2.5.1.1 Surface finish symbols 32

2.5.2 Surface Roughness 34

2.5.2.1 Surface Roughness Measurement 35 2.5.2.2 Surface Roughness Measuring Method 39 2.5.2.3 Surface Roughness Measuring Calculation 44

CHAPTER III METHODOLOGY 46

3.1 Machine Use For Machining 46

3.1.1 Conventional Lathe Machine 46

3.1.2 Computer Numerical Control (CNC) Turning Machine 47

3.2 Selection Of The Work Material 49

3.3 Selection Of Cutting Tool 50

3.4 Centre Drill And Pre -Machining Operation Procedure 51

3.4.1 Centre drill procedure 51

3.4.2 Pre machining operation procedure 53

3.5.1 Cutting speed 54

3.5.2 Cutting time 54

3.5.3 Depth of cut 55

3.5.4 Feed rate 55

3.6 Machining Operation Procedure 55

3.7 NC Code Use In The Machining 58

3.8 Experiment Analysis Method 59

3.8.1 Portable Surface Roughness Tester, SJ-301 59

3.8.1.1 Procedure 60

3.8.2 SEM Operating Parameters 61

3.8.2.1 Sequence To Operation Of The SEM 62 3.8.3 Metallurgy Microscope Operating Parameters 63

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3.10 Experiment Procedure Flow Chart 66

CHAPTER IV RESULT 67

4.1 Introduction 67

4.2 Effect of Machining/Cutting Time, T 67

4.3 Tool Wear Effect on Surface 69

4.4 Effect of Cutting Speed on Surface Profile 71

CHAPTER V DISCUSSION 75

5.1 Relationships between the surface roughness and the flank wear 75

5.2 Factors influence the surface integrity 77

5.3 Surface defects on the material after high speed machining 78

5.3.1 None continues waves on surface 78

5.3.2 Plastic deformation 80

5.3.3 Tool deposit 82

CHAPTER VI CONCLUSION 83

6.1 Conclusion 83

6.2 Recommendation 84

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LIST OF FIGURES

Figure 2.1 Schematic illustration of the basic principle of the turning

operation 8

Figure 2.2 Conventional Lathe Machine Available At UTeM 9

Figure 2.3 _{Boring Operation} 14

Figure 2.4 _{Facing Operation} 14

Figure 2.5 _{Threading Operation} 15

Figure 2.6 _{Drilling Operation} 16

Figure 2.7 Nomenclature of a general-purpose lathe toolbit 18

Figure 2.8 Cutting Tool Geometry 19

Figure 2.9 Coated Cutting Tools 27

Figure 2.10 Surface Integrity Definitions 31

Figure 2.11 Surface Finish Symbols 33

Figure 2.12 Surface Texture Symbols 34

Figure 2.13 (a) Surface Produced (b) Cross Section through Surface

Irregularities 37

Figure 2.14 Basic Characteristics Of Surface Roughness Measurement

(ASME standard B46.1, 1995) 38

Figure 2.15 Effect of Cutting Speed on the Surface Roughness of

Turned Specimens of Mild Stee 38

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Model of Surface Roughness

Figure 2.17 Measuring surface roughness with stylus 40

Figure 2.18 Path of stylus in surface roughness measurements (broken

line) compared to actual roughness profile 40

Figure 2.19 Schematic Of Stylus Profile Device For Measuring Surface

Roughness And Surface Profile With Readout Devices 41

Figure 2.20 Microtopographer, a stylus profile device used to measure

and depict surface roughness and character 41 Figure 2.21 Scanning Electron Microscope Machine 42 Figure 2.22 Example of the Surface Integrity Scan Using SEM 43

Figure 2.23 Measuring the Surface Roughness 43

Figure 2.24 Schematic for measuring the surface roughness using stylus

principle 44

Figure 3.1 Conventional lathe machine 47

Figure 3.2 CNC lathe machine 48

Figure 3.3 The Cutting Tools Specifications 50

Figure 3.4 : TiALN Coated Cutting Tool 50

Figure 3.5 Cutting tool and the holder 51

Figure 3.6 Centre drill bit 52

Figure 3.7 Center drill operation 51

Figure 3.8 Material Before Pre-Machining 53

Figure 3.9 Pre machining operation 54

Figure 3.10 Machining operation performing 56

Figure 3.11 Tied the cutting tool at the tool holder 56 Figure 3.12 Work piece clamp at the machine chuck 57

Figure 3.13 The Surf test SJ-301 59

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Figure 3.14 The surface roughness tester preparation 60

Figure 3.15 The SEM Machine Used 62

Figure 3.17 Position Of Material On The Microscope Table 64

Figure 3.16 Metallurgy microscope 64

Figure4.1 Surface Roughness vs Cutting Time Graph 69

Figure 4.2 Flank Wears vs Cutting Time Graph 71

Figure 5.1 The Relationships Between Surface Roughness Value And

The Average Flank Wear 76

Figure 5.2 None Continues Wave After 4.5 Minute Of Machining 79 Figure 5.3 None Continues Wave After 6.5 Minute Of Machining 80 Figure 5.4 Plastic Deformation After 9.5 Minute Of Machining 81 Figure 5.5 Plastic Deformation After 6.5 Minute Of Machining 81 Figure 5.6 Tool deposit After 1.0 Minute Of Machining 82

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LIST OF TABLES

Table 2.1 Types of Lathe Machine Available 11

Table 2.2 Defination Of Tool Angles 20

Table 2.3 _{Recommended tool angles for HSS and carbide} 21

Table 2.4 ISO-Recommended Roughness Values and Grade Numbers

for The Specification Of Surface Roughness 37

Table 3.1 Specifications of CNC Lathe Machine 48

Table 3.2 Nominal composition of AISI 1045 Medium Carbon Steels 49

Table 3.3 AISI 1045 Workpiece Properties 49

Table 4.1 Data for Surface Roughness 68

Table 4.2 Data for Average Flank Wear 70

Table 4.3 The Surface Texture Of The Material Using Microscope 72 Table 4.4 The Selected Surface Texture Of The Material Using

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LIST OF ABBREVIATIONS, SYMBOLS, SPECIALIZED

NOMENCLATURE

C - Constant, y intercept cutting speed at tool life of 1 minute

D - Diameter

D0 - Original diameter of workpiece, mm or in Df - Final diameter of workpiece, mm or in Davg - Average diameter of workpiece, mm or in d - Depth of cut, mm or in

F - Feed, mm/rev or in/mm

HSS - High Speed Steel l - Length of cut, mm or in

N - Rotational speed of the workpiece, rpm

n - The index for the particular combination of tool and workpiece material

MRR - mm3/min or in3/min

P - Power

SEMs - scanning electron microscopes T - Tool life in minutes

t - Time cutting, s or min

ν - Feed Rate or linear speed of the tool along workpiece length V - Cutting speed of workpiece, m/min or ft/min

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CHAPTER 1 INTRODUCTION

Machines, metalworking and machining process are among the most importance elements of modern technology. Almost every modern product manufactured worldwide relies the vast array of disciplines practiced in these three major elements.

Machining is the process of removing the unwanted material from the workpiece in the form of chip. When the process involved material such as metal, the process is often called the metal cutting or the metal removal. Material removal process and machining are indispensable to manufacturing technology. Ever since lathes were introduced in the 1700’s, many processes have been continuously developed.

Over the past few years in the manufacturing, have seen some progressed in the cutting tools technology. From the use of high-carbon steel, high-carbon speed steel, cobalt matrix and solid carbides to cemented or sintered carbides, ceramics and special cutting tools such as titanium nitride, titanium carbide and many more. All these developments have given very large advantages where we can see that the new technologies in cutting tools have been increased the production rates coupled with cost savings.

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rate, resulting in higher productivity. This has been proven beyond a doubt for the coated tungsten–carbide tools and since it has been the practice to use coated tools whenever possible to get the best performance from a cutting tool.

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.

A surface is a boundary that separates an object from another object or substance. Real surface is the actual boundary of an object. It deviates from the nominal surface as a result of the process that created the surface. The deviation also depends on the properties, composition, and structure of the material the object is made of.

1.1 Objectives

The objectives of this experiment are:

1. To study the relationship between the surfaces roughness values and turning

parameters such as cutting time during high speed machining. From the study, we were able to study whether high speed machining would able to produces better surface finish.

2. To analyzed the surface integrity of the material of high speed machining

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1.2 Scope of project

This project is about investigating the surface integrity on AISI 1045 carbon steel during turning operation using Carbide-TiC cutting tools. This study is done on the CNC lathe machine in the room temperatures. During this machining several cutting parameters such as cutting speed remains constant which is 700 rpm and they are involved such as cutting speed and cutting time.

Surface roughness tester, microscope and Scanning Electron Microscope (SEM) will be used to measure and identify the surface roughness and the surface integrity. This will determine the surface integrity of the material after completing the machining operations. The factors that influence the surface integrity and the surface roughness are 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 commonplace 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, 2001).

With the advancement of technology with the increased of development of higher grades of steel and other non-ferrous metal and high temperatures refractory materials and their application, has changed not only the technology of machining but also the development of cutting tools. In the wide development of the cutting tools, it also affects the surface of the materials that have been machined.

According to Finnie, who published a historical review of work in metal cutting (Finnie, 1956), early research in metal cutting started with Cocquilhat in 1851 (Cocquilhat, 1851) and was mainly directed toward the work required to remove a given volume of material.

In 1881, Mallock (Mallock, 1882) suggested correctly that the cutting process was basically one of the shearing the work material to form the chip and emphasized the

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importance of the effect of friction occurring on the cutting-tool face as the chip removed.

Today’s coating technology has contributed significantly to the advancement of materials for the metal-cutting industries. Various coatings, especially those obtained by using PACVD (plasma assisted chemical vapour deposition) and PVD (physical vapour deposition), have been found to enhance tool life and increase cutting speed and feed-rate, resulting in higher productivity (To¨nshoff et al, 1997).

Several studies were carried out in order to determine the relationship between process parameters and layer properties on the last few years and surface integrity of the substrate material is important in order to meet the demands of sufficient coating adhesion (Gebauer et al, 1997). The surface technologies have been increased due to the development of the cutting tools and machine tools.

Turning is the one of the operation that involved in the material removal or cutting operation. Turning means that the part is rotating while it is being machined. (Kalpakjian, 2001). Turning is then divided into two main processes which is roughing and finishing.

In the roughing operation, the surface of working material usually is roughness and not smooth surface because roughing is the first operation in turning before perform the finishing operation. Mean-while in the finishing process, it is a process which it involved small amount of material removal in one time and main purposed of this process is to get better finish of the materials.

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2.2 COMMON MACHINE TOOLS

Machine tools are generally powered-driven metal-cutting or forming machines used to shape metal by:

I. The removal of chips

II. Pressing, drawing or shearing

III. Controlled electrical machining processes

Any machine tools generally have the capability of:

I. Holding and supporting the workpiece II. Holding and supporting a cutting tool

III. Imparting suitable movement (rotation or reciprocating) to the cutting tool or the work

IV. Feeding the cutting tool or the work so that the desired

cutting action and will be achieved

The machine industry is divided into several different categories, such as the general machine shop, the tool room and the production shop. The machine tools found in the metal trade fall into three broad categories:

1. Chip-producing machines, which form metal to size and shape by cutting away

the unwanted sections. These machine tools generally alter the shape of the steel products by casting, forging or rolling in a steel mill.

2. Non-chip-producing machines, which form metal to size and shape by pressing, drawing, punching or shearing. These machine tools generally alter the shape of the sheet steel products and also produce parts which need little or no machining by compressing granular or powdered metallic materials.

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3. New-generation machines, which were developed to perform operations, would be very difficult, if not impossible to perform on chip- or non-chip producing machines. Electro-discharge, electro-chemical and laser machines, for example, use either electrical or chemical energy to form metal to size or shape.

2.3 MACHINING OPERATION– TURNING LATHE

For this project, the main machining operation involved is the turning process. Turning is the machining operation that produces cylindrical parts. In its basic form, it can be defined as the machining of an external surface, it is performed on a machine called a lathe in which the tool is stationary and the part is rotated. The operation involved the following:

• The workpiece is rotated,

• Using a single-point cutting tool, and

• With the cutting tool feeding parallel to the axis of the workpiece and at a

distance that will remove the outer surface of the work

Turning constitutes the majority of lathe work. The cutting forces resulting from the feeding the tool from right to left and be directed towards the headstock to force the workpiece against the workholder. The single-point tool is moved parallel to machine spindell for straight or contour turning of the outside diameter. From the tools, both flat and circular, were at one time fed into the workpiece to produce the desired contour of the part.

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Figure 2.1: Schematic illustration of the basic principle of the turning operation (Efunda Engineering Fundamental, 2006).

2.3.1 The Basic Parts of Lathe Machine

In the lathe machine it is divided into five main parts. The five main parts of the lathe are:

I. the bed, II. the headstock, III. the carriage, IV. the tailstock,

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1.2 Scope of project

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CHAPTER 2 LITERATURE REVIEW

2.1 INTRODUCTION

According to Finnie, who published a historical review of work in metal cutting (Finnie, 1956), early research in metal cutting started with Cocquilhat in 1851

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importance of the effect of friction occurring on the cutting-tool face as the chip removed.

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2.2 COMMON MACHINE TOOLS

Machine tools are generally powered-driven metal-cutting or forming machines used to shape metal by:

I. The removal of chips

II. Pressing, drawing or shearing

III. Controlled electrical machining processes Any machine tools generally have the capability of:

I. Holding and supporting the workpiece II. Holding and supporting a cutting tool

III. Imparting suitable movement (rotation or reciprocating) to the cutting tool or the work

IV. Feeding the cutting tool or the work so that the desired cutting action and will be achieved

1. Chip-producing machines, which form metal to size and shape by cutting away the unwanted sections. These machine tools generally alter the shape of the steel products by casting, forging or rolling in a steel mill.

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2.3 MACHINING OPERATION– TURNING LATHE

• The workpiece is rotated,

• Using a single-point cutting tool, and

• With the cutting tool feeding parallel to the axis of the workpiece and at a distance that will remove the outer surface of the work

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Figure 2.1: Schematic illustration of the basic principle of the turning operation

(Efunda Engineering Fundamental, 2006).

2.3.1 The Basic Parts of Lathe Machine

In the lathe machine it is divided into five main parts. The five main parts of the lathe are:

I. the bed, II. the headstock, III. the carriage, IV. the tailstock,

Surface Integrity Of AISI 1045 Steel When Machined With TiC Cutting Tool.

UNIVERSITI TEKNIKAL MALAYSIA MELAKA