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1 DEDICATION A special thanks to Dr. Mohammed gogazeh for his invaluable work assistance without his guidance and great supervision, this work would never be accomplished. Thanks and appreciation to the Mechanical Engineering Department instructors at Philadelphia University. I would like to introduce my thanks to my Family.

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DEDICATION

A special thanks to Dr. Mohammed gogazeh for his invaluable work assistance

without his guidance and great supervision, this work would never be

accomplished.

Thanks and appreciation to the Mechanical Engineering Department instructors at

Philadelphia University.

I would like to introduce my thanks to my Family.

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ACKNOWLEDGMENT

I would like to express my special thanks of gratitude to Dr. Mohammed gogazeh

who gave me the golden opportunity to do this wonderful project on the topic,

which also helped me in doing a lot of Research and I came to know about so many

new things I am really thankful to him.

Secondly I would also like to thank my parents and friends who helped me a lot in

finalizing this project within the limited time frame.

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ABSTRACT

The study of the mechanical properties of aluminum alloy 6063 during the

extrusion process.

study of how to extrusion. And the steps going through the metal, and study the

effect of forces on the metal by solid work program.

By gathering information from the factory ,studied the sample. The result:

Knowledge of the properties and the results of tests done on the sample and its

success.

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CONTENTS

DEDICATION …………………………………………………………………………………… 1

ACKNOWLADGEMENT ……………………………………………………………………….. 2

ABSTRACT ……………………………………………………………………………………… 3

LIST OF TABLES ……………………………………………………………………………….. 5

LIST OF FIGURES ……………………………………………………………………………… 6

1.0. INTRODUCATION ………………………………………………………….…………. 7

1.1. The basic properties of aluminum ……………………………………………………….. 7

1.2. Structure of aluminum …………………………………………………………………... 8

1.3. Aluminum transformation ………………………………………………………………. 9

1.4. Aluminum Alloys: Aluminum 6063/6063A Properties, Fabrication and Applications... 10

2.1. Why Aluminum Hot Extrusion ……………...………………………………… 12

2.2. Billet Preheating……………………………………………………………………….. 12

2.3. Extrusion……………………………………………………………………………….. 14

2.4. Quenching……………………………………………………………………………… 15

2.5. Stretching……………….……………………………………………………………… 15

2.6. Cut Off……………………..……………………………………………………………17

2.7. Artificial Aging………………………………………………………………………….17

3.1. Extrusion Pressure Calculations…………………………………………………………18

3.2. Extrusion Exit Speed Estimation……………………………………………………….. 19

4.1. Simulation…………………………………………………………………………….... 21

4.1.1. fatigue test……………………………………………………………………….. 21

4.1.2. static stress test…………………………………………………………………... 23

4.1.3. Thermal test……………………………………………………………………… 24

5.1. Arab aluminum industry factory (ARAL)

5.1.1Aluminum melting process………………………………………………………25

5.1.2 The cooling process…………………………………….……….………………26

5.1.3 Extrusion process by extruding device………………………………………….27

References ……………………………………………………………………………28

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LIST OF TABLES

Table 1.1: Chemical composition for aluminum alloy 6063 and 6063 9

Table 1.2: Mechanical properties for aluminum alloy 6063 10

Table 2.1: Typical Heat Treatment Parameters of some 6xxx alloys 16

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LIST OF FIGURES

Figure 2.1: Process Map and Layout for an Aluminum Hot Extrusion Installation 12

Figure 2.2: Billet-on-billet extrusion using welding plate in front of the die 13

Figure 3.1: Limit Diagram for Extrusion Speed 19

Figure 4.1: simulation fatigue test for alloy 20

Figure 4.2: FOS for alloy when tested by fatigue test 21

Figure 4.3: simulation for static stress test 22

Figure 4.4: simulation thermal convection test 23

Figure 5.1: The degree of melting temperature 24

Figure 5.2: The cooling process for aluminum 24

Figure 5.3: pressure 210 for extrusion 25

Figure 5.4: the pumps 25

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1.0 Introduction:

Physically, chemically and mechanically aluminum is a metal like steel, brass, copper, zinc, lead

or titanium. It can be melted, cast, formed and machined much like these metals and it conducts

electric current. In fact, often the same equipment and fabrication methods are used as for steel.

1.1 The basic properties of aluminum:

Light Weight:

Aluminum is a very light metal with a specific weight of 2.7 g/cm3, about a third that of steel.

For example, the use of aluminum in vehicles reduces dead-weight and energy consumption

while increasing load capacity. Its strength can be adapted to the application required by

modifying the composition of its alloys.

Corrosion Resistance:

Aluminum naturally generates a protective oxide coating and is highly corrosion resistant.

Different types of surface treatment such as anodizing, painting or lacquering can further

improve this property. It is particularly useful for applications where protection and conservation

are required.

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Electrical and Thermal Conductivity:

Aluminum is an excellent heat and electricity conductor and in relation to its weight is almost twice as

good a conductor as copper. This has made aluminum the most commonly used material in major power

transmission lines.

Reflectivity:

Aluminum is a good reflector of visible light as well as heat, and that together with its low

weight, makes it an ideal material for reflectors in, for example, light fittings or rescue blankets.

Ductility:

Aluminum is ductile and has a low melting point and density. In a molten condition it can be

processed in a number of ways. Its ductility allows products of aluminum to be basically formed

close to the end of the product’s design.

1.2 Structure of aluminum:

Aluminum is a metallic element, and its structure is very similar to most other metals. It is

malleable, and ductile due to its polycrystalline structure. Aluminum is made up of grains (or

crystals) which interlock when the metal is cooled from molten. Each grain comprises of rows of

atoms in an ordered lattice arrangement, giving each grain an isotropic (same in each direction)

structure. Although the different grains are somewhat randomly arranged with grain boundaries

forming during the cooling process, the atoms within each crystal are normally aligned which

makes the whole metal isotropic, like the individual grains.

However, despite a regular lattice arrangement gaps in between atoms often form, which give

rise to dislocations This is shown in the image above where the point of the dislocation is marked

with a red line. When stress is applied to the metal the atoms move past each other one by one to

move these dislocations to the grain boundaries. This effect is extremely important in fracture

mechanics and it gives aluminum so many of its important properties. The image on the left

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shows the next positions of the atoms after some stress has been applied. It is clear that the blue

atoms have been forced across to next to the orange ones, and that the dislocation (shown with

red line) has moved the other way.

1.3 Aluminum transformation:

Extrusion: A solid aluminum cylinder called a billet (available in a variety of alloys,

pretreatments and dimensions), is heated and squeezed through a die with a shaped opening to

create a desired profile. Extrusions are widely used in construction, road and rail applications.

Casting: Using either sand casting or die casting techniques, the aluminum is shaped

according to a mold.

Rolling: Aluminum passes through a hot-rolling mill and is then transferred to a cold-rolling

mill, which can gradually reduce the thickness of the metal down to as low as 0.05 mm. Rolled

products are categorized as either foil (less than 0.2 mm thick), sheet (0.2-6 mm), or plate

(thicker than 6 mm).

Aluminum and recycling:

Fully recyclable with no downgrading of quality, aluminum is the most cost-effective material to

recycle. In fact, 75% of the aluminum produced since its discovery is still in use today.

Using aluminum, industries can attain their overall recycling targets. In parallel, the aluminum

industry is also constantly developing and refining its recycling processes.

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1.4 Aluminum Alloys: Aluminum 6063/6063A Properties,

Fabrication and Applications:

Aluminum alloy 6063 is a medium strength alloy commonly referred to as an architectural alloy.

It is normally used in intricate extrusions.

It has a good surface finish, high corrosion resistance, is readily suited to welding and can be

easily anodized. Most commonly available as T6 temper, in the T4 condition it has good

formability.

Applications of 6063 Aluminum:

Architectural applications

Extrusions

Window frames

Doors

Shop fittings

Irrigation tubing

Road transport

Element 6063 % Present 6063A % Present

Si 0.2 to 0.6 0.3 to 0.6

Fe 0.1 to 0.35 0.15 to 0.35

Cu 0.05 to 0.1 0.15

Mn 0.05 to 0.1 0.15

Mg 0.45 to 0.9 0.6 to 0.9

Zn 0.05 to 0.1 0.1 to 0.15

Ti 0.002 to 0.1 0.2

Cr 0.05 max 0.06

Al Balance Balance

Table 1.1 Chemical composition for aluminum alloy 6063 and 6063A

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Temper Proof

Stress

0.20%

(MPa)

Tensile

Strength

(MPa)

Shear

Strength

(MPa)

Elongation

(%)

Elongation

(%)

Hardness

Brinell

HB

Hardness

Vickers

HV

Fatigue

(MPa)

0 50 100 70 27 26 25 85 110

T1 90 150 95 26 24 45 45 150

T4 90 160 110 21 21 50 50 150

T5 175 215 135 14 13 60 65 150

T6 210 245 150 14 12 75 80 150

T8 240 260 155 9 80 85

Table 1.2 Mechanical properties for aluminum alloy 6063

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2.1 Why Aluminum Hot Extrusion?

Among the different types of existing extrusion processes, Hot Extrusion is the most

commonly used in the industry. Aluminum and aluminum alloys are the most ideal

materials for extrusion, and they are the most commonly extruded. The most important

and common method used in aluminum extrusion is the Direct (or Forward) Process. The

majority of the commercially available aluminum alloys in the 1xxx, 3xxx, 5xxx, and 6xxx series

are easily extruded. Of these, the predominant alloy group by commercial volume (covering

about 80% of all extruded products) is the 6xxx series alloys, with Aluminum 6063 being by

far the first in the list, followed by Aluminum 6061. The high-strength aluminum

alloys in the 2xxx and 7xxx series are more difficult to extrude, but still can be extruded with the

proper procedures.

The hot extrusion process map for aluminum alloys is illustrated in Figure 3.1, where a

typical installation layout is shown. The seven main steps of the process [6] consist of: 1)

Preheating the Billet, 2) Extrusion, 3) Quenching, 4) Stretching, 5) Cut-off, 6) Artificial Aging

and

7) Quality Control. The following sections explain the details of each of the steps in the process.

2.2 Billet Preheating

The preheating of the billet is done either in a Gas Furnace or in an Electrical Induction

Heater. The Induction Furnace is the most technically efficient unit for billet heating

Available. The basic structure of a low-frequency induction heater consists of a horizontal

coil in which three or four billets are heated to the desired temperature in a continuous cycle

. The typical billet temperatures for the so called soft and medium-grade aluminum alloys

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(most of 1xxx, 3xxx, 5xxx, 6xxx series) are shown in Table 3.1, while Table 3.2 shows the same

information for the so called hard aluminum alloys (2xxx, 7xxx and some 5xxx series). In

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order to make sure the billet has attained thermal equilibrium (i.e. a steady state temperature

profile) in the time available between extrusions, the electrical power of the coil is increased as

necessary. The time required to heat the billet is mainly a function of the thermal

conductivity of the alloy, the billet dimensions and the electrical power input. The time

between loading the billet and its removal can vary from 3 to 20 minutes. In some cases,

depending on the press capacity, several furnaces are installed to feed one press. On the

other hand, the high-speed gas furnace represents a cheaper energy alternative, but cannot

equal the heating speed of the induction furnace, with heating period times being three to five

times longer

Figure 2.1 Process Map and Layout for an Aluminum Hot Extrusion Installation

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2.3 Extrusion

The second step in the process map of Figure 1.1 is the Extrusion operation, which

begins with loading the preheated billet in the press container, then extruding it until a

specified billet butt thickness is left over. Stopping extrusion at a specified butt thickness

prevents oxide and other metallic or nonmetallic inclusions from flowing into the extrusion.

According to industry practice, standard butt thickness for direct extrusion is kept to

~10% of the billet length. Next, the press container and the ram are retracted and the

butt is cutoff by a shear and then recycled. Once the container and ram have returned to their

original positions, the process is repeated. In order to improve productivity, a “billet-on-billet”

extrusion process is generally used to produce continuous lengths of a given section. In

this process, the butt discard is removed as mentioned before, and then the following billet is

welded (in a solid state weld, with the aid of temperature and pressure) to the one remaining in

a welding or feeder plate, as shown in Figure 1.2. Aluminum alloys are well suited to this

process, as they are easily welded at the extrusion temperature and pressure. The billet

on-billet method makes extrusion a continuous manufacturing process, in which the length of

the continuous extruded is limited only by the length of the runout table (shown in Figure 1.1),

which is usually between 30-40 m.

Figure 2.2 Billet-on-billet extrusion using welding plate in front of the die

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2.4 Quenching

The third step in the process map of hot extrusion is the quenching operation. Water-spray

systems are gradually replacing tank-type water quench and over-table and under-table cooling

fans. High-pressure, high velocity sprays have been developed to quickly cool difficult shapes

well below critical temperatures to attain higher mechanical properties and desired finish. High

pressure Spray Quench offers the maximum cooling rate in a profile while also minimizing

distortion, thus allowing maximum extrusion speed with minimum space requirements.

2.5 Stretching

After quenching, the extruded material generally requires straightening to remove the

distortion and residual stresses generated during the cooling operation. The sections are

transferred from the runout and cooling table to the stretcher bed to be straightened by

stretching 1 to 3%. The stretcher capacity has to be greater than the required stretching

force, which is the product of the cross sectional area of the shape times the yield strength of

the alloy. Current technology for precise control of gripping pressure prevents the

stretcher both from excessively distorting the extrusion and from allowing slippage at the grip,

hence, minimizing scrap and manual intervention. where the significant deformation imposed on

the gripped part of the extrusion is evident.

Note that, depending on the size of the cross section, more than one extrusion at a time can be

straightened by the stretcher. Nowadays, stretching equipment offers one, two, or no-man

operational modes, reducing labor costs of the extruder

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2.6 Cut off

Sawing is the next operation after stretching. A high-speed circular cutoff saw is

normally used to trim stretcher grip marks, front and back end allowances and to cut the

extrusion to the finished lengths. The sawing principle is illustrated, where it

can be seen that the sections are moved against a gage stop, which is set to the required length

of the product. Saw chips are collected by using a high-pressure vacuum connected to the

machine. Also, as in the stretching operation, the sawing operation can cut off a batch of

extrusions simultaneously, depending on the size of the section, the alloy and the capacity of

the saw

2.7 Artificial Aging

Artificial Aging is the final stage of the heat treatment process and is used to achieve the

desired temper for the alloy. Typical Heat Treatment parameters for some 6xxx alloys are

shown in Table 2.1. It is important to remark that precipitation hardening is a two stage-process,

starting with Solution.

Heat Treatment and followed by Precipitation Heat Treatment (aging). For the soft and

medium-grade aluminum alloys the Solution Heat Treatment stage is carried out inside the

press during the hot extrusion and the subsequent quenching. Thus, when the extrusion

exits the press, its temperature shall be no lower than the one specified in Table 3.3 for the

Solution Heat Treatment to be effective. Otherwise, a separate out-of-the line Solution Heat

Treatment needs to be carried out, reducing the productivity of the process. That is sometimes

the case for aluminum extrusions made of hard alloys.

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Table 2.1 Typical Heat Treatment Parameters of some 6xxx alloys

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3.1 Extrusion Pressure Calculations

While there are numerous models in the literature for predicting the pressure that is

necessary to extrude a part, one of the most commonly used in practice due to its simplicity is:

where po is the pressure required to extrude a round billet into a solid round bar with an

Extrusion Ratio of R=Ao/Af (Ao being the billet cross sectional area, and Af being the extrusion

cross sectional area); σf is the flow stress of the material at the extrusion temperature and

strain rate; Lo and Do are the billet length and diameter respectively and mf is a friction factor

that ranges from zero to one (mf=0 for a frictionless case, and mf=1 for a sticking friction case).

In non-lubricated extrusion (as it is the case for aluminum alloys), sticking friction at the billet

container interface is generally assumed (worst-case scenario), and therefore mf=1. The flow

stress σf of the material can be estimated by the typical hot working constitutive equation:

where C and m are temperature dependent material properties called Strength Coefficient and

Strain Rate Sensitivity Exponent, respectively.

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The strain rate 𝜀 is calculated as an average effective value by the following expression:

where vo is the extrusion ram speed, which is related to the extrusion exit speed vf and the

extrusion ratio R, by the mass conservation principle in the following form:

where the extrusion exit speed (vf) is dictated by the extrudability of the alloy (i.e. the

Maximum exit speed it can sustain without surface tearing)

3.2 Extrusion Exit Speed Estimation

the extrusion exit speed is a crucial parameter in the extrusion process, having both technical and

economical relevance. Besides its influence on the strain rate (and thus on the flow stress and

extrusion pressure), the extrusion exit speed has a direct impact on the productivity of the

process (i.e. on the cycle time), so it is desirable to maximize it without compromising the

quality of the extruded part.

This tradeoff is illustrated in Figure 2.1, in the form of a Limit Diagram for Extrusion Speed,

based on the extrusion capability of the press (which increases with temperature) and the

metallurgical capability against hot shortness of the alloy (which is reduced with temperature).

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The maximum extrusion speed depicted in Figure 2.1 is a theoretical value that would be

obtained only if the optimal exit temperature is maintained, which is hardly ever the case.

Figure 3.1 Limit Diagram for Extrusion Speed

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4.1 simulation

4.1.1 fatigue test:

This test 's Framework window made of aluminum.

The imposition of power worth 2 kg, The pressure 10,000 times by hand & 10,000 times close and open.

Figure 4.1 simulation fatigue test for alloy

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Factor of safety (FOS)

After placing the sample in all possible circumstances, you will find FOS is 1.

Figure 4.2 FOS for alloy when tested by fatigue test

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4.1.2 static stress test

Is installed, the forces on the edges

Figure 4.3 simulation for static stress test

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4.1.3 Thermal test

We put in the far room temperature rises and the summer is 30 degrees Celsius.

Heat transfer coefficient (h) of air from 10 – 100, We have had imposed 15 W/(m2•K).

Figure 4.4 simulation thermal convection test

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5.1 Arab aluminum industry factory (ARAL)

5.1.1Aluminum melting process:

Figure 5.1The degree of melting temperature

5.1.2 The cooling process:

Figure 5.2 The cooling process for aluminum

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5.1.3 Extrusion process by extruding device

The aluminum extrusion machine under the pressure of 210 bar, By 3 pumps.

Figure 5.3 pressure 210 for extrusion

Figure 5.4 the pumps

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References

1. https://www.ideals.illinois.edu/bitstream/handle/2142/16501/TorreNieto_Jose.pdf?seque

nce=3

2. http://www.azom.com/article.aspx?ArticleID=2812

3. http://www.european-aluminium.eu/talat/lectures/1501.pdf

4. http://sam.davyson.com/as/physics/aluminium/site/structure.html

5. M. Zehetbauer, W. Pfeiler, and J.Schrank (1983): “Micro hardness and Yield stress of

Cold Rolled Pure Aluminum up To very High Deformation”. Scripta Metallurgica,

Vol.17, pp 221-226, 1983.

6. C .A. Mitchell and A. M. Davidson (2000): “Effect of Al203 particulates as

reinforcement in age hard enable aluminum alloy composites”. Materials Science and

Technology, 2000, 16 (07) 873 – 876.

7. - McDowell, D. L. (2000). “Modeling and experiments in plastering”. Solids and

structures 371 (1 -2), Pg. 293 -309.

8. W.S. Lee, W. C. Sue, C.F. Lin and C. J. WU (1999): “Effect of aging on high strain

rate a n d h i g h t e m p e r a t u r e of 7 0 7 5 a l u m i n u m s alloy”. Materials

S c i e n c e a n d Technology, 1999, 151 (12) 1379 -1386.

9. - Ming Dao and Ming Lie (2001): “A micromechanics study on strain-localization-

induced fracture initiation in bending using crystal plasticity models”. Philosophical

Magazine A, 2001, Vol.81, NO.8, 1997-2020