MECHANICAL PROPERTIES OF DISSIMILAR · PDF file · 2016-05-25Report submitted in partial fulfillment of the requirements ... Tesis ini membentangkan penyelidikan mikrostruktur dan

MECHANICAL PROPERTIES OF DISSIMILAR ALUMINUM-BASED ALLOY JOINTS BY MIG WELDING

AHMAD DANIAL BIN ABDULLAH

Report submitted in partial fulfillment of the requirementsfor the award of the degree of

Bachelor of Mechanical Engineering with Mechanical Engineering

Faculty of Mechanical EngineeringUNIVERSITI MALAYSIA PAHANG

JUNE 2012

vi

ABSTRACT

This thesis deals with the investigation of microstructure and mechanical properties of weld joint of AA5052-H32 and AA6061-T6 aluminum alloys by using MIG welding process. The objective of this thesis is to investigate the effect of parameters to the mechanical properties and microstructure of AA5052-H32 and AA6061-T6. The thesis describes the proper MIG welding process using automatic table in order to investigate the effect on microstructure and mechanical properties of weld joint of AA5052-H32 and AA6061-T6. The aluminum ER5356 was used as filler in this experiment. The studies of mechanical properties that are involved in this thesis consist of toughness, tensile strength of AA5052-H32 and AA6061-T6 weld joint before and after MIG welding process. Four different parameters were used in order to determine the correlation between mechanical properties and microstructure of the weld joint. As aresult, it is observed that the current is the parameter which has the highest influence to the UTS and toughness and it is followed by torch angle, speed and lastly weld passes.The optimum parameter for the highest value of UTS and toughness is found; current=90A, torch angle=+15, speed=4mm/s and weld pass=1. The microstructure shows crack sensitivity and porosity which decreases the strength and toughness of weld joint. As for the recommendation, the other properties including hardness, corrosion resistance should be considered in order to optimally select a material for its specific application.

vii

ABSTRAK

Tesis ini membentangkan penyelidikan mikrostruktur dan ciri-ciri mekanikal logam kimpalan aluminium AA5052-H32 dan aluminium AA6061-T6 dengan menggunakan proses MIG welding. Objektif tesis ini ialah mengkaji kesan setiap parameter yang berlainan ke atas mikrostruktur dan ciri-ciri mekanikal logam kimpalan yang menggabungkan aluminium AA5052-H32 dan AA6061-T6. Selain itu, tesis ini juga menerangkan proses MIG welding yang betul dengan menggunakan meja automatikbagi menghasilkan logam kimpalan yang berkualiti. Antara skopnya ialah logam isianER5356 digunakan untuk memastikan gabungan yang baik terhasil antara kedua-dua aluminium. Antara spesifikasi projek ini adalah merangkumi ciri-ciri mekanikal yang terdiri daripada kekerasan dan kekuatan tensil. Oleh yang demikian , empat jenis parameter proses telah ditetapkan bagi mengkaji dan memenuhi spesifikasi projek ini. Keputusan yang diperoleh membuktikan bahawa parameter yang berbeza mampu mempengaruhi cirri-ciri mekanikal dan mikrostruktur logam kimpalan tersebut. Dalam kajian dari segi mikrostrukturnya, ia membuktikan bahawa kehadiran kesan keretakan dan ruang-ruang udara member kesan ke atas kekuatan tensil dan kekerasan logam kimpalan yang terhasil. Secara konklusinya, kita perlu menjalankan kajian ke atas ciri mekanikal yang lain seperti ketahanan daripada karat dan kekuatan dimana ia dapat dihasilkan dalam kombinasi terbaik untuk kegunaan bidang kejuruteraan.

viii

TABLE OF CONTENTS

Page

SUPERVISOR’S DECLARATION ii

STUDENT’S DECLARATION iii

DEDICATION iv

ACKNOWLEDGEMENTS v

ABSTRACT vi

ABSTRAK vii

TABLE OF CONTENTS viii

LIST OF TABLES xi

LIST OF FIGURES xiii

LIST OF ABBREVIATION xvi

CHAPTER 1 INTRODUCTION

1.1 Background Studies 1

1.2 Problem Statements 2

1.3 Project Objectives 3

1.4 Project Scopes 3

1.5 Overview of Report 3

CHAPTER 2 LITERATURE REVIEW

2.1 Introduction 4

2.2 Aluminum Alloys 4

2.2.1 Types of Aluminum Alloys 52.2.2 Intermetallic Compound (IMC) 7

2.2.3 Aluminum AA6061-T6 and AA5052-H32 9

2.3 MIG Welding Process 13

2.3.1 Equipment 14 2.3.2 Welding Gun 16 2.3.3 Power Supply 16

2.3.4 Electrode 172.3.5 Shielding gas 17

ix

2.3.6 Operation 17

2.4 Mechanical Testing 18

2.4.1 Charpy Test 18 2.4.2 Tensile Test 20

2.5 Taguchi Approach 21

CHAPTER 3 METHODOLOGY

3.1 Introduction 24

3.2 Flow Chart 25

3.3 Flow Chart Description 26

3.3.1 Design Selection 26

3.3.2 Preparation of Specimen 30

3.3.3 Preparation of Welds 30

3.3.4 Welding Process 30

3.3.5 Polishing Process 31

3.3.6 Optical Investigation 33

3.3.7 Mechanical Testing 34

3.3.8 Analysis of Experimental Data 36

CHAPTER 4 RESULTS AND DISCUSSION

4.1 Introduction 39

4.2 Mechanical Properties 39

4.2.1 Tensile Strength 40 4.2.2 Charpy Toughness 43 4.2.3 Effect of Speed,Torch Angle Current, 43

Weld Pass to UTS and Toughness

4.3 Taguchi Method 47

4.3.1 ANOVA 47 4.3.2 Main Effect Plot 49 4.3.3 Regression Analysis 50 4.3.4 Contour Plot and Surface Plot for Charpy Toughness 53 4.3.5 Contour Plot and Surface Plot for UTS 57 4.3.6 Experimental Data and Predicted Data Comparison 60

4.4 Microstructure Observation 63

x

4.4.1 Microstructure 63 4.4.1 Defect in Weld Joint 66

CHAPTER 5 CONCLUSION AND RECOMMENDATIONS

5.1 Introduction 69

5.2 Conclusions 69

5.3 Future Recommendations 70

REFERENCES 71

APPENDICES 73

A Gant Chart

xi

LIST OF TABLES

Table No. Title Page

2.1 Aluminium alloys in space frame car design in Europe and North America

5

2.2 Classification of aluminum alloys 6

2.3 Microstructure of AA6061-T6 and AA5052-H32 -11 10

2.4 Composition of AA5052-H32 and AA6061-T6-12 11

2.5 Mechanical Properties of AA5052-H32 and AA6061-T6 -13 11

2.6 Properties of AA5052-H32 and AA6061-T6 -14 12

2.7 Example of process parameter: Injection moulding parameters and their levels

21

2.8 Experimental plan using L9 orthogonal array 22

2.9 Example of ANOVA: ANOVA table for bending test 24

3.1 Welding Test Result 27

3.2 Parameter of Experiment 28

3.3 Design of experiment using Taguchi Method by using Mixed Level Design – L18 (2 levels 1 columns + 3 levels 3 column)

28

3.4 Analysis of Variance (ANOVA) of UTS vs Speed; Welding pass; Current; Torch angle

38

4.1 Mechanical Properties of AA6061-T6 and AA5052-H32 Weld Metal (weld joint)

40

4.2 ANOVA 48

4.3 Rank of every parameter based on the Taguchi Analysis;Combination of UTS & Toughness vs Speed; Welding pass; Current; Torch angle

48

4.4 Comparison of results with mean predicted value 51

4.5 Factor levels for predictions based on Taguchi Method 51

xii

4.6 Predicted values of S/N ratio, Mean and Standard Deviation based Taguchi Method

52

4.7 Predicted Data versus Experimental Data 60

xiii

LIST OF FIGURES

Figure No. Title Page

2.1 The eutectic particles of 6082 alloy 8

2.2 Eutectic region of aluminum 6XXX 8

2.3 Eutectic region in 5XXX 9

2.4 Phase diagram of Aluminum 5XXX 13

2.5 Phase diagram of 6XXX 13

2.6 MIG Circuit diagram 14

2.7 GMAW torch nozzle cutaway image 15

2.8 GMAW weld area 18

2.9 Charpy test 19

2.10 Stress-strain curve 20

2.11 Example for main effect graph 22

3.1 Process flow chart of study 25

3.2 (a) Weld specimen for Charpy’s Test, (b) Weld specimen for

Tensile Test

29

3.3 a) Aluminum AA5052-H32 and b) AA6061-T6 sheet 30

3.4 a) Power supply, b) Automatic Working Table 31

3.5 Polisher-grinder Meserv for various size 32

3.6 Optical Microscope 33

3.7 a) Charpy’s Test machine, b) Swinging Pendulum 34

3.8 Charpy Test Specimen 34

3.9 Tensile Test Machine 35

3.10 Specimen of Tensile Test (ASTM E8M-04) -43 35

xiv

4.1 Graph UTS value versus experiment number 40

4.2 Graph Stress versus Strain; a) Exp. 1 for minimum UTS, b) Exp.

9 for medium UTS, c) Exp. 6 for maximum UTS

42

4.3 Charpy value versus experiment number 43

4.4 Weld toe angle 45

4.5 weld toe of specimen: a) Experiment 1, b) Experiment 6 and c)

Experiment of optimize value parameter

46

4.6 Double weld passes of experiment 14 specimen 47

4.7 Graph of Main Effect Plot for S/N Ratio 49

4.8 Main Effect Plot for Mean 50

4.9 Crack Profile of tensile specimen based on optimum parameter 52

4.10 Crack Profile of Charpy’s test specimen based on the optimum

parameter

53

4.11 (a) contour plot: Charpy’s toughness vs current; speed, (b)

surface plot: Charpy’s toughness vs current; speed

54

4.12 (a) contour plot: Charpy’s toughness vs current; torch angle, (b)

surface plot: Charpy’s toughness vs current; torch angle

55

4.13 (a) contour plot: Charpy’s toughness vs torch angle; speed, (b)

surface plot: Charpy’s toughness vs torch angle; speed

56

4.14 (a) contour plot: UTS vs current; speed, (b) surface plot: UTS vs

current; speed

57

4.15 (a) contour plot: UTS vs torch angle; current, (b) surface plot:

UTS vs torch angle; current

58

4.16 (a) contour plot: UTS vs torch angle, speed, (b) surface plot: 59

xv

UTS vs torch angle; speed

4.17 Experimental UTS versus predicted UTS 61

4.18 Experimental charpy toughness versus predicted charpy

toughness

62

4.19 Microstructure of; a) AA5052-H32 microstructure, b) AA6061-

T6 microstructure by magnification of 50X.

63

4.20 Porosity in Weld metal (WM) microstructure 64

4.21 Heat affected zone (HAZ) and fusion zone (FZ) in

Microstructure

65

4.22 Fusion zone of 6061 welds 66

4.23 Porosity in weld metal zone of 6061 welds 67

4.24 Crack sensitivity in weld joint of 6061 microstructure 68

xvi

LIST OF ABBREVIATIONS

AA Aluminum alloy sheet

T6 A type of heat treatment process

H32 A type of hardening process

ASTM American Society for Testing and Materials

MIG Metal inert gas

TIG Tungsten inert gas

DOE Design of experiment

UTS Ultimate tensile strength

CTE Coefficient thermal expansion

AC Alternating current

DC Direct current

SMAW Shielded metal arc welding

DF Degree of freedom

SM Sum of squares

MS Mean square

F F-function

SSR Sum of square regression

SSE Sum of square error

SST Sum of square total

1

CHAPTER 1

INTRODUCTION

1.1 BACKGROUND

This thesis is about the investigation of weld joint (dissimilar Aluminum alloys)

microstructures and mechanical properties using MIG welding process. Aluminum is

the second important after steel usage because of its characteristic which is high

strength stiffness to weight ratio, good corrosion resistance, good formability better

conductor of heat and electricity. It has been the best candidate to replace heavier

material like steel and copper in automobile because it has the recycling potential. The

choice of material is influenced by the requirement to improve the economy of fuel and

also the energy consumption.

For example, automotive companies have been given mandate by US

Government that they need to minimize vehicle exhaust emission, enhance fuel

economy and improve occupant safety (W.S. Miller, 2000). In automotive industry,

welding of dissimilar parts of different weld will be much needed because each part

(inner and outer panel consist of different aluminum alloys) of car needs to be joined

together. The increasing of aluminum and magnesium alloys is mainly caused by the

rapid growth of application of material that has the light weight characteristic (D.-

A.Wang, 2007). And for this study, MIG (metal inert gas) welding process is chosen to

join the welds.The material that will be used is Aluminum alloy AA5052-H32 series

and 6061-T6 series for the experiment because they are often used in the industry (W.S.

Miller, 2000). While the microstructure and mechanical properties investigation consists

of tensile strength, toughness and corrosion resistance of the weld before welding

process and weld metal (WM) after MIG welding process.

2

1.2 PROBLEM STATEMENT

Aluminum alloys may often be used to replace steel in many applications

especially in automotive industry welding process (W.S. Miller, 2000). But, the

problem is the high difference of thermal conductivity of different aluminum alloys

using MIG or TIG will cause problems (Luijendijk, 2000). The lack of fusion of

material or excessive melting of material that has lower thermal conductivity is caused

by the larger thermal conductivity in arc that flow in material. The other problem in

MIG welding between dissimilar weld relates to the transition zone between the metals

and the intermetallic compounds (IMC) that produced in this transition zone.

It is very important to investigate the phase diagram of the two metals for the

fusion type welding process like MIG welding process. The dissimilar joints only can

be made successfully if there is mutual solubility exist between both aluminum alloys.

No solubility between the aluminum alloys can give the problem to the joint process.

The intermetallic compound formed between dissimilar weld need to be investigated to

check their crack sensitivity, ductility and susceptibility to corrosion, etc. The

microstructure views need to be done observe the eutectic phase in the intermetallic

compound.

The other factor causes problem to the welding of dissimilar aluminum alloys

relates to the thermal coefficient of thermal expansion (CTE) of both welds (Luijendijk,

2000). The widely difference between both thermal coefficient of thermal expansion

can cause the internal stresses set up in the IMC zone during any temperature change of

the welding process. The service failure may soon occur if there is extreme brittleness

characteristic in intermetallic zone. The last factor is melting temperatures of the two

aluminum alloys (Luijendijk, 2000). If there are differences in melting point, it will

cause the other problem. This is of primary interest when a welding process utilizing

heat is involved since one metal will be molten long before the other when subjected to

the same heat source. The high heat input of welding will make the weld has advantage

when welds of different melting temperature and thermal expansion to be joined.

3

1.3 OBJECTIVES

The objectives of this project are:

1) To investigate the effect of parameters; torch angles, speeds, welding passes and

currents to the mechanical properties of weld joints.

2) To predict the optimum parameters based on Taguchi methods analysis and

verified with experimental

3) To study the different of mechanical properties and microstructure of weld joint

(AA5052-H32 and 6061-T6 aluminum alloys) using the different welding

parameters.

1.4 SCOPE OF PROJECT

The scopes of the project are:

1) Welding process of different Aluminum alloys

2) Tensile and impact test investigation

3) Microstructure Analysis of weld joint (weld metal)

1.5 OVERVIEW OF REPORT

Chapter 1 mainly briefs about the background of the project which involves the

introduction, problem statements, objectives and scopes of the report. Chapter 2

basically describes more about the studies on microstructure, mechanical properties of

aluminum alloy which has been done earlier by other scientists and engineers and

Taguchi Method. Whereas Chapter 3 introduces the experimental procedure utilized to

characterize the aluminum alloys studies the step by step process that will be done

during this project and steps to perform Taguchi analysis with experimental values.

Chapter 4 mainly discuss about the results obtained during the experiment. Lastly,

Chapter 5 discuss about the conclusions that can be derived from this report and suggest

few future recommendations.

4

CHAPTER 2

LITERATURE REVIEW

2.1 INTRODUCTION

In this chapter, it basically describes more about the studies on microstructure

and mechanical properties of aluminum alloys which has been done earlier by other

scientists and engineers. Therefore, it also discussed about the MIG welding process

which has been used in this experiment.

2.2 ALUMINUM ALLOYS

The typical alloying elements usually consist of copper, magnesium, manganese,

silicon, zinc, etc. Aluminum alloy is classified into two principal namely casting alloys

and wrought alloys that consist of the heat-treatable and non-heat-treatable. About 85%

of aluminum used for wrought products. For example is foils, rolled plate and foils.

Aluminum alloys are mainly used in the components and engineering structures

that required the light weight and high corrosion resistance of material. Alloys

composed of aluminum and magnesium have been used widely in aerospace

manufacturing because of light weight features. Aluminum 5xxx is lighter than other

aluminum alloys. It also less flammable than aluminum alloys that contained high

percentage of magnesium. Outstanding bare metal corrosion of the 5xxx and 6xxx

aluminum materials is the obvious and significance difference between aluminum and

steel (W.S. Miller 2000). Table 2.1 shows the applications of aluminum 5xxx and 6xxx

in automotive industries.

5

Table 2.1: Aluminium alloys in space frame car design in Europe and North America,

Parts Europe North AmericaOuter Panels 6061-T4 6111-T4

Inner Panels 5051/5182/6181A 6111/2008/5182

Structure/Sheet 6XXX-T4 5754-O

Structure/Extrusion 6XXX 6XXX

Source: W.S. Miller (2000)

2.2.1 Types of Aluminum Alloys

There are many types of aluminum alloys. It consists of heat treatable and non-

treatable aluminum alloys. Table 2.2 shows the types of aluminum alloys and its

classification.

6

Table 2.2: Classification of aluminum alloys

Series Properties1xxx It contains 99% of Aluminum Non-heat treatable

2xxx Aluminum Copper approximation 2 -10%. Strength and allows precipitation hardening. Weld solidification crackingcan occurs.

Heat treatable

3xxx Aluminum Manganese. It increasesstrength.

Non-heat treatable

4xxx Aluminum Silicon. It can reduce meltingtemperature and can be heat treated alloy when combined with magnesium.

Both heat treatable and none-heat

treatable

5xxx Aluminum Magnesium. It increases strength.

None-heat treatable

6xxx Aluminum Magnesium plus Silicon. It creates a unique compound magnesium silicide Mg2Si and suitable for extrusion components. It has heat treat properties.

Heat treatable

7xxx Aluminum Zinc. It provides a heat treatable aluminum alloy which has very high strength when zinc copper and magnesium is added. Stresscorrosion cracking and some alloys can be weld using MIG and some cannot.

Heat treatable

Source: Electric, L (2009)

a) None Heat Treatable Aluminum Alloys

Cold working or strain hardening process can increase strength of this type of

aluminum alloys. Mechanical deformation will occur in the aluminum structure in order

to reach the desired strength and it will cause the increasing of resistance to strain

producing both higher and lower ductility. Non-heat treatable alloys cannot get high

strength characteristics of heat treatable precipitation-hardened alloys. The absence of

precipitate-forming elements in the low-to-moderate strength becomes beneficial for a

welding perspective. This is because many of alloy additions needed for heat treatable

precipitation hardening, magnesium plus silicon or copper plus magnesium can lead to

hot cracking during solidification in welding process.

7

b) Heat treatable aluminum alloys

Different from non-heat treatable alloys, heat treatable aluminum alloy achieve

their optimum mechanical properties by thermal controlled heat treatment. The 2xxx,

6xxx and 7xxx series are heat treatable aluminum alloys where 4xxx series consist of

heat treatable and non-heat treatable alloys. It tends to undergo hot cracking. Heat

treatable alloys get their mechanical properties by solution heat treatment, thermal

treatment and artificial aging are the most common methods.

2.2.2 Intermetallic Compound (IMC)

Intermetallic compound in aluminum AA5052-H32 and AA6061-T6 need to be

observed before the experiment is performed. For example for this observation,

aluminum 6082 is chosen to be example for this study (G. Mrowka-Nowotnlk, 2007).

There are three types of eutectic particles in the intermetallic compounds that is consist

of α, β and the Mg2Si as shown in the Figure 2.1(a) and 2.1(b).

(a)

8

Figure 2.1: The eutectic particles of 6082 alloy in: a) ternary eutectic, b) the quaternary

eutectic

Source: G. Mrowka-Nowotnlk 2007

Mg2Si appeared in this microstructure view of 6082 because Si is the important

element in the aluminum 6xxx as AA6061-T6. This is shown in Figure 2.2.

Figure 2.2: Eutectic region of aluminum 6xxx

Source: Donald R. Askeland 2002

(b)

9

The Mg2Si possibly not appear in the aluminum 5xxx series as AA5052-H32

because Si is not the major element. This is shown in Figure 2.3.

Figure 2.3: Eutectic region in 5xxx

Source: Donald R. Askeland 2002

2.2.3 Aluminum AA6061-T6 and AA5052-H32

There are a few things that must be reviewed in both aluminums which is

chemical composition, mechanical properties, thermal properties, etc. This is to make

sure the factor that will give the problem to the welding process of both materials.

2.2.3.1 Composition of AA6061-T6 and AA5052-H32

The microstructure of the aluminum AA6061-T6 and AA5052-H32 is shown in

the Table 2.3. It seems that there is a difference in the grain size of both alloys. The

grain size may be one of a factor that can be considered can affect the mechanical

properties of aluminum alloys.

10

Table 2.3: Microstructure of AA6061-T6 and AA5052-H32

Aluminum Alloys

Micrograph (room temp.)

AA5052-H32

AA6061-T6

Source: S. Mahabunphachai (2010)

The composition of both alloys is shown in the Table 2.4. ER5356 filler

composition also put in the table to compare its composition with both AA5052-H32

and AA6061-T6. As mentioned before (refer to Table 2.2), the AA5052-H32 has more

magnesium composition than AA6061-T6. But the ER5356 contains highest

magnesium composition compared to both alloys. AA6061-T6 has the highest

composition of Silicon compared to AA5052-H32 and ER5356. The composition of

both aluminums also must be considered to make sure that the continuity can be success

in the weld materials.

11

Table 2.4: Composition of AA5052-H32 and AA6061-T6

Alloys Elements and weight percentage (wt%)Al Cr Cu Fe Mg Mn Si Ti Zn Be Other

AA5052-H32

95.7 -97.7

0.15 -0.35

Max 0.1

Max 0.4

2.2-2.8

Max 0.1

Max 0.25

- Max 0.1

- Max 0.15

AA6061-T6

95.8-98.6

0.04-0.35

0.15-0.4

Max 0.7

0.8-1.2

Max 0.15

0.4-0.8

Max 0.15

Max 0.25

- Max 0.15

ER 5356 92.9 -95.3

0.05 -0.2

0.1 0.4 4.5-5.5

0.05- 0.2

Max0.25

0.06-0.2

Max 0.1

Max 0.000

8

Max 0.15

Source: Metal Handbook 10th (1990)

The ultimate tensile strength (UTS) of AA6061-T6 is higher than AA5052-H32.

This can be seen in the Table 2.5. The table shows the other mechanical properties like

hardness, fatigue strength of AA5052-H32, AA6061-T6 and also the filler used in this

welding.

Table 2.5: Mechanical Properties of AA5052-H32 and AA6061-T6

Mechanical Properties AA6061-T6 AA5052-H32

Filler 5356

Hardness, Brinell 95 60 -Hardness, Vickers 107 83 -Tensile Strength, Ultimate (MPa) 310 228 -Tensile Strength, Yield (MPa) 276 193 -Modulus of Elasticity (GPa) 68.9 70.3 70Poissons Ratio 0.330 0.330 0.330Fatigue Strength (MPa) 96.5 117 -Machinability 50% 30% -Shear Modulus (GPa) 26.0 25.9 26Shear Strength (MPa) 207 138 -

Source: Metal Handbook 10th (1990)

The other important mechanical property that must be considered is melting

point because it will cause the problem to the weld dilution if the both weld has the big

difference in boiling point. It seems like there is no big difference between AA5052-

H32 and AA6061-T6 in boiling point as shown in the Table 2.6. This means that the

12

joining process of these two different welds can be successful because they will melt at

the almost same temperature. The CTE values are also not very different in both

materials as shown in the table. The thermal stress will not be the problem to welding

process in this study.

Table 2.6: Thermal Properties of AA5052-H32 and AA6061-T6

Thermal Properties AA6061-T6 AA5052-H32 ER 5356

CTE, linear (µm/m-°C) 23.6 @Temperature 20.0 - 100 °C

23.8 µm/m-°C@Temperature 20.0 - 100 °C

24.1 µm/m-°C@Temperature 20.0 - 100 °C

Specific Heat Capacity (J/g-°C)

0.896 0.880 0.904

Thermal Conductivity (W/m-K)

167 138 116

Melting Point (°C) 582 - 651.7 607.2-649 571-635Solidus (°C) 582 607.2 571Liquidus (°C) 651.7 649 635

Source: Metal Handbook 10th (1990)

2.2.3.2 Phase diagram of AA5052-H32 and AA6061-T6

Figure 2.4 shows the phase diagram of aluminum 5xxx series and the eutectic

particles α, β and (α + β) in the aluminum 5xxx series. Figure 2.5 shows the eutectic

region in the aluminum 6xxx series and the eutectic particles α, β and (α + β) in the

aluminum 6xxx series.