Comparison Study Between The Effect Of Vortex Air Cooling And Conventional Cooling On Flank Wear And Surface Roughness.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

COMPARISON STUDY BETWEEN THE EFFECT OF VORTEX

AIR COOLING AND CONVENTIONAL COOLING ON FLANK

WEAR AND SURFACE ROUGHNESS

This report submitted in accordance with requirement of the Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering

(Manufacturing Process) (Hons.)

YAP HUI MEI B051110109 910504-05-5164

FACULTY OF MANUFACTURING ENGINEERING 2015

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS LAPORAN PROJEK SARJANA MUDA

TAJUK: Comparison Study between the Effect of Vortex Air Cooling and Conventional

Cooling on Flank Wear and Surface Roughness

SESI PENGAJIAN: 2014/15 Semester 2

Saya YAP HUI MEI

mengaku membenarkan Laporan PSM ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Laporan PSM 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 ini sebagai bahan pertukaran antara institusi pengajian tinggi.

4. **Sila tandakan ( )

SULIT

TERHAD

/ TIDAK TERHAD

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

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

________________________________ Alamat Tetap:

LOT 12193 KAMPUNG BARU 28380 KEMAYAN

PAHANG.

Tarikh: 30 JUN 2015

Disahkanoleh:

________________________________ Cop Rasmi:

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DECLARATION

I hereby, declared this report entitled “Comparison Study between the Effect of Vortex Air Cooling and Conventional Cooling on Flank Wear and Surface Roughness” is the result of my own research except as cited in references

Signature :

Author’s Name : Yap Hui Mei Date : 30 JUNE 2015

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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) (Hons.). The member of the supervisory is as follow:

…….……….. (Project Supervisor)

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ABSTRAK

Cecair pemotong dalam proses beralih digunakan untuk mengurangkan suhu pemotongan antara mata alat and serpihan. Pemesinan hijau amat disukai, dengan itu penyejukan tiub vorteks adalah diperkenalkan. Penyejukan udara mendorongkan penurunan suhu antara mata alat and serpihan. Cecair pemotong konvensional menyebabkan impak kesihatan, pencemaran dan kos yang tinggi dalam aspek pembelian dan rawatan. Terdapat satu kajian korelasi di antara tekanan udara dan suhu udara vorteks dalam eksperimen pertama, manakala perbandingan kehausan rusuk dan kekasaran permukaan antara penyejukan udara vorteks dan penyejukan konvensional dalam eksperimen kedua. Suhu udara vorteks telah diukur oleh Hanna K-type thermocouple. Dalam eskperimen kedua, proses pemesinan dilakukan dalam parameter yang dioptimumkan serta tetap, 425rpm kecepatan pemotongan, 0.05mm/rev kecepatan dan 0.5mm kedalaman pemotongan. Mesin Larik adalah digunakan untuk proses pemesinan, manakala Stereo Microscope dan Mitutoyo profilometer digunakan mengukur kehausan rusuk serta kekasaran permukaan masing-masing. Coefficient of determinant, R2 dalam eksperimen pertama berhampiran dengan 1, bermakna satu hubungan yang kuat antara tekanan udara dan suhu udara vorteks. Berdasarkan analisis ANOVA, eksperimen kedua menunjukkan kedua-dua bendalir pemotong menjejaskan kehausan rusuk dan kekasaran permukaan dengan signifikasi. Penyejukan secara konvensional membekalkan kehausan rusuk sebanyak 2.4 kali lebih kecil daripada penyejukan udara vorteks. Ini kerana kekonduksian haba dan perolakan haba pekali udara adalah rendah daripada cecair. Namun, penyejukan udara vorteks mempunyai kekasaran permukaan dengan 60% lebih rendah daripada penyejukan konvensional kerana lazim kemunculan “built up edge” semasa menggunakan penyejukan konvensional.

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ABSTRACT

In turning process, cutting fluid is used to reduce cutting temperature at tool-chip interface. A green machining is always preferable, so vortex air cutting is introduced. Vortex air helps to reduce cutting temperature at the tool-chip interface, without using cutting fluid that caused health hazard, pollution and a high cost have to spend on purchasing and treatment. Cold air is produced by compressed air without using any refrigerant and it is used to spot onto tool-workpiece interface. First experiment studied correlation between air pressure and vortex air temperature, while second experiment compared the flank wear and surface roughness between both vortex air cooling and conventional cooling. Vortex air temperature was measured by Hanna K-type thermocouple. For the second experiment, optimized machining parameters were used which are high cutting speed of 425rpm, low feed rate of 0.05mm/rev and 0.5mm depth of cut. A lathe machine, a Stereo Microscope and a Mitutoyo profilometer were used for machining, measuring flank wear as well as surface roughness respectively. The coefficient of determinant, R2 of first experiment is closed to 1 which means a strong correlation between air pressure and vortex air temperature. Based on ANOVA analysis, the second experiment indicated that both coolant type significantly influenced flank wear and surface roughness. For flank wear performance, conventional cooling was 2.4 times smaller than that of vortex air cooling. The main reason is the air is a poorer heat conductivity and lower specific heat convection. However, vortex air cooling made an improvement of 60% on surface roughness when compared to that of conventional cooling. This is because built up edge was prevalent for conventional cooling.

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DEDICATION

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ACKNOWLEDGEMENT

First and foremost, I would like to show my sincere gratitude to my supervisor, Associate Prof Dr Md Nizam Bin Abd Rahman who always takes time to support and guide me throughout this research. In addition, I am so grateful to the Manufacturing Engineering Faculty of UTeM who always provides laboratory and equipment to support me for accomplishing this study. Besides, my sincere thanks to engineering assistants who willing to give me information about the equipment and supervise me in the lab sessions. I have been blessed with my classmates who willing to take time to discuss the final year project. Last but not least, a special thanks to my parent and family who encourage me throughout my undergraduate study.

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TABLE OF CONTENT

ABSTRAK i

ABSTRACT ii

DEDICATION iii

ACKNOWLEDGEMENT iv

TABLE OF CONTENT v

LIST OF TABLES ix

LIST OF FIGURES xi

LIST OF EQUATIONS xiv

LIST OF ABBREVIATIONS xv

CHAPTER 1: INTRODUCTION 1

1.1 Background of Cutting Fluid 1

1.2 Problem Statement 2

1.3 Objectives of Research 3

1.4 Scope of Research 4

1.5 Hypothesis 4

CHAPTER 2: LITERATURE REVIEW 5

2.1 Machining 5

2.1.1 Milling 6

2.1.2 Drilling 6

2.1.3 Boring 7

2.1.4 Grinding 7

2.1.5 Turning 7

(a) Machining Conditions 9

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(d) Conventional Cutting Fluid 16

(e)Cutting tool material 17

(f) Workpiece material 18

2.2 Dry Machining/Alternatives 19

2.2.1 Compressed Air Cooling/Vortex Air 20

(a) Principle of Vortex Tube 20

(b) Relationship between Pressure and Outlet Air Temperature 22

2.3 Summary of Journals 24

2.4 Strategy of Inferential Statistics 35

2.4.1 Null Hypothesis and Alternative Hypothesis 35

2.5 Strategy of Statistical Test 38

2.5.1 Analysis of Variance (ANOVA) 38

2.5.2 Pearson Product Moment Coefficient of Correlation 39

2.5 Summary 40

CHAPTER 3: METHODOLOGY 41

3.1 Work Flow of Research 41

3.2 Vortex Air Pressure and Temperature Correlation Study 43

3.2.1 Apparatus 43

3.2.2 Procedure of Experiment 44

3.3 Comparison Study between Vortex Air Cooling and Conventional Cutting Fluid 45

3.3.1 Experimental Setup 45

(a) Turning Operation 45

(b) Input Parameters 46

(d) Workpiece 49

3.3.2 Experimental Procedure 50

(a) Preliminary Study for Material Removal Volume 50

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3.4 Data Collection 53 3.4.1 Vortex Air Pressure and Temperature Correlation Study 53 3.4.2 Comparison Study between Vortex Air Cooling and Conventional Cutting Fluid

(a) Maximum Flank Wear, VBmax 54

(b) Average Surface Roughness, Ra 55

3.5 Correlation Analysis 56

3.5.1 Vortex Air Pressure and Temperature Correlation Study 57 3.5.2 Comparison Study between Vortex Air Cooling and Conventional Cutting Fluid

CHAPTER 4: RESULT AND DISCUSSION 59

4.1 Vortex Air Pressure and Temperature Correlation Study 59 4.1.2 Comparison Study between Vortex Air Cooling and Conventional Cutting Fluid

62 4.2 Comparison Study between Vortex Air Cooling and Conventional Cutting Fluid 62 4.2.1 Preliminary Study for Material Removal Volume 62

4.2.2 Flank Wear 66

4.2.3 Surface Roughness, Ra 71

4.3 Other Considerations in Machining Process 78

4.3.1Cost and Waste Management 78

4.3.2 Safety, Health and Environment Problem 79

CHAPTER 5: CONCLUSION AND FUTURE WORK 82

5.1 Conclusion 82

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REFERENCES 84 APPENDICES

A.Cutting insert

C. Composition of Cutting Fluid D. Result of Vortex Air Temperature

E.Flank Wear on Conventional Cutting Fluid Conventional Cutting Fluid F. Flank Wear under Vortex Air Cooling

E. Surface Roughness, Ra G. Gantt Chart PSM

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LIST OF TABLES

2.1 Recommended Cutting Speed Regarding to Material 9 2.2 Common Type of Single Point Cutting Tools 18 2.3 Mechanical Properties of AISI 1018 Mild Steel 19

2.4 Performance Data of Vortex Tube 23

2.5 Summary of Previous Experiments 24

2.6 Outcome of Hypothesis Testing 36

2.7 Types of Error and Measurements of Error 37

3.1 Specifications of Apparatus 43

3.2 The Effect of Air Pressure on Average Temperature 44

3.3 Specifications f Momac Lathe Machine 46

3.4 Input Parameters Used in This Study 47

3.5 Mechanical Properties of Uncoated Tungsten Carbide, G10E 48 3.6 ISO Nomenclature of Tungsten Carbide 48

3.7 Nominal Composition of Cutting Tool 49

3.8 Composition of AISI 1018 Mild Steel 49

3.9 Mechanical Properties of AISI 1018 Mild Steel 50 3.10 Flank Wear and Surface Roughness of Each Coolant 52

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3.11 Specifications of Meiji Stereo Microscope 54

3.12 Specifications of Profilometer SJ-301 56

4.1 Appropriate Length of Inner Diameter of Hose for Compressed Air Line 62

4.2 Total Material Removal Volume 64

4.3 Flank Wear of Conventional Cutting Fluid and Vortex Air Cooling 66 4.4 ANOVA Analysis on Flank Wear between Two Samples (Part 1) 68 4.5 ANOVA Analysis on Flank Wear between Two Samples (Part 2) 68 4.6 Average Surface Roughness for Conventional Cutting Fluid and Vortex

Air Cooling 73

4.7 ANOVA Analysis on Surface Roughness between Two Samples (Part 1) 74 4.8 ANOVA Analysis on Surface Roughness between Two Samples (Part 2) 74

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LIST OF FIGURES

2.1 Illustration of Turning Process 8

2.2 Effect of Parameters on Machining Performance 8

2.3 Distribution of Primary Tool Wear 11

2.4 Flank Wear 13

2.5 Schematic of Flank Wear 13

2.6 Tool Wear Measurement According to ISO 3685:1993 14 2.7 Variation of Ra of Uncoated Carbide in Dry, Wet and Cryogenic Cooling

Machining 15

2.8 Types of Cutting Fluid 16

2.9 Generation of High Rotating Speed Air 21

2.10 Higher Moving Air Discharged and Slower Moving Air Rotated Back to

Center 21

2.11 Heat Transfer from Slower Moving Air to Higher Incoming Air 21 2.12 Separated Air Temperature on Cold End and Hot End of Vortex Tube

According to Several Pressure Level 22

2.13 Ra Value in Both Wet Machining and Dry Machining with Different Parameters 27

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2.15 Flank Wear Land Width (VB) in Different Conditions at V=300m/min and

f=0.055 mm/rev 32

2.16 Flank Wear Land Width (VB) in Different Conditions at V=186m/min and

f=0.155 mm/rev 33

2.17 Maximum Flank Wear Produced under Three Variables 34

3.1 Flow Chart for Study 42

3.2 Momac Conventional Lathe Machine 45

3.3 Classification of Turning Insert Grades 47

3.4 Calculation of Material Removal Volume 51

3.5 Set Up of Vortex Air Cooling Experiment 53

3.6 Meiji Stereo Microscope 54

3.7 Tool Measurement of VBmax 55

3.8 Mitutoyo Profilometer with Model SJ 301 56

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4.1 Relationship between Air Pressure and Vortex Air Temperature 60 4.2 Average Temperature of April 2015 in Malacca 61 4.3 Flank Wear versus Material Removal Volume for Both Coolants 65 4.4 Graph of Flank Wear for Conventional Cutting Fluid and Vortex Air

Cooling 69

4.5 Graph of Surface Roughness for Conventional Cutting Fluid and Vortex

Air Cooling 75

4.6 Built-Up-Edge on Flank Face under Conventional Cutting Fluid

Condition 77

4.7 Chips are Flushed Away from Interface under Vortex Air Cooling

Condition 78

4.8 Chips are Jammed at the Interface under Conventional Cooling Condition 78 4.9 Preparation of Cutting Fluid before Starting Experiment 80

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LIST OF EQUATIONS

2.1 Formula of Cutting Speed in m/min 10

2.2 Formula of Depth of Cut 11

2.3 Null Hypothesis, H0:A B 35

3.1 Conversion from m/min to rpm 47

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LIST OF ABBREVIATIONS

FR Resultant Force

H0 Null hypothesis

H1 Alternative hypothesis

mm millimeter

MQL Minimum quantity lubrication R2 Coefficient of Determination Ra Surface roughness

rpm Revolution per minute VBB Flank Wear-Land Width

VBmax Maximum Flank Wear

α Alpha β Beta

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CHAPTER 1 INTRODUCTION

This chapter briefly explained the background of cutting fluid in machining, problem statement, objectives of research, scope of research and its hypothesis.

1.1 Background of Cutting Fluid

Friction is generated at the tool-chip interface during machining process and it produced high temperature on the cutting tool. Wear is accelerated at elevated temperature, subsequently cutting tool life is decreased. Besides, the surface roughness is increased, whilst dimensional sensitiveness of workpiece is decreased due to generated friction (Cakir et al., 2007)(Boswell and Chandratilleke, 2009). Cakir et al.(2007) pointed out that there are some approaches to protect cutting tools from heat generation. For example, the cutting tool can be coated with heat resistance alloys such as titanium alloy. From economical perspective, conventional coolant is one of the more economical approach to reduce the heat generation and increase material removal rates. Basically, coolant is used to cool cutting tool and workpiece as well as lubricates them. Besides, it flushes the chips away from the cutting zone. The cooling effect plays the most important role to decrease temperature on the cutting zone so that longer tool life, high dimensional accuracy and good surface quality of machined workpiece are achieved. Water based coolant is more suitable for turning process due to high cutting

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speed. A high pressure cutting fluids with additive is utilized in steel machining. However, this method causes some problems, such as mixture of sulphur (cutting fluid) and oils (additive) left stain over the workpiece’s surface. The used cutting fluid usually consists of fine chip, tramp oil and contaminants (Chowdhury et al., 2014).

Although, conventional coolant has a lot of benefits, it is unfriendly to environment and produces biological hazards to operators. An alternative is approached to solve this problem during machining process, which is dry machining. Dry machining is the machining process without using any coolant which can address concerns regarding to environmental legislation (Cakir et al., 2007 and Duspara et al., 2013). Sharma et al. (2009) stated that there are some techniques that can be used to replace the conventional cutting fluid during dry machining. For example, minimum quantity lubrication (MQL), compressed air cooling, cryogenic cooling and high pressure coolant. They have a potential to reduce the friction and heat at cutting zone as well increase material removal rate. According to Duspara et al. (2013), a stream of cold air from vortex tube spots onto interface between tool tip and workpiece can reduce the tool wear and machining cost.

1.2Problem Statement

Boswell and Chandratilleke (2009) indicated that air cooling method is seldom being considered in manufacturing industry because of the effectiveness of conventional cutting fluid during machining process. However, usage conventional cutting fluid is harmful the environment and create the health hazards to human being. In addition to that cost for conventional cutting fluid is quite high. Dangar and Mukherjee (2014) stated that dry machining should be given a lot of awareness for sake of environment and workers’ health. Mac (2012) said that those that were exposed cutting fluids for a long period of time have higher probability to suffer from a lot of diseases. He gave an example of illness suffered by workers in Birmingham in year 2004. Around 70 workers

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at a car engine factory were diagnosed with serious lung illness. In addition, the Health and Safety Executive (HSE) had screened over 1000 workers of Powerstrain in Longbridge Plant, Birmingham. It was found that 73 people were definitely had suffered occupational asthma or extrinsic allergic alveolitis and worried about the outbreak of occupational lung disease among workers. Accordingly, HSE advised Powerstrain to take a serious improvement on the cleaning and monitoring regimes for the metalworking machines and cutting fluids. HSE discovered that microbes in cutting fluids resulted in diseases and need to be controlled.

Apart from the negative environmental and health impacts, the cost of conventional cutting fluid is quite high which is around 7-17% of total machining cost. Selek et al. (2011) said the cutting become polluted during machining process. Actually, only 15% of cutting fluid is used to dissipate heat, another 1% sticks onto part which may influence the quality of part and the rest cutting fluid is returned back to oil tank, and remained in cooling oil to avoid a contact with air. This step resulted in the thriving condition for bacteria to breed in the cooling oil. So, another economic burden associated to usage of cutting fluid was to establish regular cleaning of cooling tank and treatment. Moreover, cutting fluids have to change regularly due to their low efficiency after being used for a certain time.

1.3Objectives of Research

Objectives of this research are:

 To study the correlation between inlet air pressure and the vortex outlet air temperature.

 To compare the effectiveness of vortex air cooling to that of conventional cutting fluid with respect to flank wear and surface roughness.

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1.4Scope of Research

There are two experiments executed for this project. The first experiment was done to determine the minimum temperature that can be achieved using available compressed air using vortex tube. The second experiment focused on the effectiveness of vortex air cooling on the flank wear and surface roughness of workpiec. Other input variables which are cutting speed, feed rate and depth of cut were set at constant values. The cutting tool was tungsten carbides, the workpiece was mild steel.

1.5 Hypothesis

The hypothesis testing is to investigate the effect of conventional coolant and vortex air cooling to tool flank wear and surface roughness. Null hypothesis, H0 and alternative

hypothesis, H1 specify the relationship between conventional coolant ad vortex air

cooling.

H0 : flank wear (vortex air cooling) = flank wear (conventional cooling)

H1 : flank wear (vortex air cooling) ≠ flank wear (conventional cooling)

H0 : surface roughness (vortex air cooling) = surface roughness (conventional cooling)

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CHAPTER 2 LITERATURE REVIEW

This chapter described machining process, especially turning operation. Next, dry machining is introduced in term of vortex air. Then, some information was collected from journals with similar scope as that of this study. Lastly, the strategy of inferential statistic and statistical test were briefly explained.

2.1 Machining

According to Kaushish (2010), machining is a process that involves removes material and transforms the machined product into desired size and shape. Machining includes a huge number of cutting operations. The basic machining includes milling, drilling, boring grinding, turning and etc.

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LIST OF ABBREVIATIONS

FR Resultant Force

H0 Null hypothesis

H1 Alternative hypothesis

mm millimeter

MQL Minimum quantity lubrication

R2 Coefficient of Determination

Ra Surface roughness

rpm Revolution per minute

VBB Flank Wear-Land Width

VBmax Maximum Flank Wear

α Alpha

β Beta

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CHAPTER 1

INTRODUCTION

This chapter briefly explained the background of cutting fluid in machining, problem statement, objectives of research, scope of research and its hypothesis.

1.1 Background of Cutting Fluid

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1.2Problem Statement

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1.3Objectives of Research

Objectives of this research are:

 To study the correlation between inlet air pressure and the vortex outlet air temperature.

 To compare the effectiveness of vortex air cooling to that of conventional cutting fluid with respect to flank wear and surface roughness.

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1.4Scope of Research

1.5 Hypothesis

The hypothesis testing is to investigate the effect of conventional coolant and vortex air cooling to tool flank wear and surface roughness. Null hypothesis, H0 and alternative

hypothesis, H1 specify the relationship between conventional coolant ad vortex air

cooling.

H0 : flank wear (vortex air cooling) = flank wear (conventional cooling)

H1 : flank wear (vortex air cooling) ≠ flank wear (conventional cooling)

H0 : surface roughness (vortex air cooling) = surface roughness (conventional cooling)

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CHAPTER 2

LITERATURE REVIEW

2.1 Machining

Comparison Study Between The Effect Of Vortex Air Cooling And Conventional Cooling On Flank Wear And Surface Roughness.

UNIVERSITI TEKNIKAL MALAYSIA MELAKA