material process

8/7/2019 material process

1/24

1

Content

Title Pages

Introduction 3

Topic

1.Metal working processes 4

Hot working 4

Cold working 4

Extruding 6

Welding 7

Brazing/Soldering 8

2.Treatment method 9

Hardening 9

Tempering 10

Anealling 11

Normalizing

Case hardening 13

3.Composite process 14

Wet lay-up 14

Prepreg lay up 15

Filamnet winding 15

Press molding 16

Resin transfer molding(RTM) 17


2/24

2

Resin infusion 18

Chopper gun sprayed materials 19

KOBELCO 20

Conclusion 23

Bibliography 23


3/24

3

Introduction

The manufacturing process is divided into three,first is metalworking process, metalworking, rolling is a

metal forming process in which metal stock is passed through a pair of rolls. Rolling is classified

according to the temperature of the metal rolled. If the temperature of the metal is above its

recrystallization temperature, then the process is termed as hot rolling. If the temperature of the metal is

below its recrystallization temperature, the process is termed as cold rolling. Second is treatment

method,Heat Treatment is the controlled heating and cooling of metals to alter their physical and

mechanical properties without changing the product shape. Heat treatment is sometimes done

inadvertently due to manufacturing processes that either heat or cool the metal such as welding or

forming,And lastly is composite process,A comprehensive overview of composite manufacturing

processes. For each method, we discusses the process, raw materials and molds, crosslinking, component

characteristics, and applications.


4/24

4

1.Metal working processes

y Hot working

Hot working refers to processes where metals are plastically deformed above their

recrystallization temperature. Being above the recrystallization temperature allows the material to

recrystallize during deformation. This is important because recrystallization keeps the materials

from strain hardening, which ultimately keeps the yield strength and hardness low and ductility

high.This contrasts with cold working.

y Cold workingA material is considered to be cold worked if its grains are in a distorted condition after plastic

deformation is completed. All the properties of a metal that are dependent on the lattice structure are

affected by plastic deformation or cold working. The following properties are affected by cold work

significantly:

Tensile Strength Hardness Yield Strength Ductility


5/24

5

Tensile strength, yield strength and hardness are increased, while ductility is decreased.

Although both strength and hardness increase, the rate of change is not the same.

Hardness generally increases most rapidly in the first 10 percent reduction (cold work),

whereas the tensile strength increases more or less linearly. The yield strength increases

more rapidly than the tensile strength, so that, as the amount of plastic deformation is

increased, the gap between the yield and tensile strengths decreases. This is important in

certain forming operations where appreciable deformation is required. In drawing, for

example, the load must be above the yield point to obtain appreciable deformation but

below the tensile strength to avoid failure. If the gap is narrow, very close control of the

load is required.

Effect of cold working on tensile and yield strength of copper.


6/24


7/24


8/24

8

y Brazing/Soldering

Brazing joins two pieces of base metal when a melted metallic filler flows across the joint and

cools to form a solid bond. Similar to soldering, brazing creates an extremely strong joint, usually

stronger than the base metal pieces themselves, without melting or deforming the components.

Two different metals, or base metals such as silver and bronze, are perfect for brazing. Use this

method to make a bond that is invisible, resilient in a wide range of temperatures, and can

withstand jolting and twisting motion.

The process of brazing is the same as soldering, although metals and temperatures differ.Y

ou canbraze pipes, rods, flat metals, or any other shape as long as the pieces fit neatly against each other

without large gaps. Brazing handles more unusual configurations with linear joints, whereas most

welding makes spot welds on simpler shapes.


9/24

9

2.Treatment method

y Hardening

Hardening involves heating a steel to its normalising temperature and cooling (Quenching )

rapidly in a suitable fluid e.g oil, water or air.

Steel is basically an alloy iron and carbon some steels alloys have have various other elements in

solution. When steel is heated above the upper critical temperature (about 760oC), the iron

crystal structure will change to face centered cubic (FCC), and the carbon atoms will migrate into

the central position formerly occupied by an iron atom. This form of red-hot steel is called

austentite ( iron). If this steel form cools slowly, the iron atoms move back into the cube

forcing the carbon atoms back out, resulting in soft steel called pearlite. If the sample was

formerly hard, this softening process is called annealing.

If the steel is cooled quickly (quench) by immersing it in oil or water, the carbon atoms are

trapped, and the result is a very hard, brittle steel. This steel crystal structure is now a body

centered tetragonal(BCT) form called martensite.


10/24

10

y TemperingAfter the hardening treatment is applied, steel is often harder than needed and is too brittle for most

practical uses. Also, severe internal stresses are set up during the rapid cooling from the hardening

temperature. To relieve the internal stresses and reduce brittleness, you should temper the steel after it is

hardened. Tempering consists of heating the steel to a specific temperature (below its hardening

temperature), holding it at that temperature for the required length of time, and then cooling it, usually

instill air. The resultant strength, hardness, and ductility depend on the temperature to which the steel is

heated during the tempering process.

The purpose of tempering is to reduce the brittleness imparted by hardening and to produce definite

physical properties within the steel. Tempering always follows, never precedes, the hardening operation.

Besides reducing brittleness, tempering softens the steel. That is unavoidable, and the amount of hardness

that is lost depends on the temperature that the steel is heated to during the tempering process. That is true

of all steels except high-speed steel. Tempering increases the hardness of high-speed steel.


11/24

11

y Annealing

Full annealing is the process of slowly raising the temperature about 50 C (90 F) above theAustenitic

temperature line A3 or line ACM in the case of Hypoeutectoid steels (steels with < 0.77% Carbon) and 50

C (90 F) into the Austenite-Cementite region in the case of Hypereutectoid steels (steels with > 0.77%

Carbon).

It is held at this temperature for sufficient time for all the material to transform into Austenite or

Austenite-Cementite as the case may be. It is then slowly cooled at the rate of about 20 C/hr (36 F/hr) in

a furnace to about 50 C (90 F) into the Ferrite-Cementite range. At this point, it can be cooled in room

temperature air with natural convection.

The grain structure has coarse Pearlite with ferrite or Cementite (depending on whether hypo or hyper

eutectoid). The steel becomes soft and ductile


12/24

12

y NormalizingNormalizing is the process of raising the temperature to over 60 C (108 F), above line A3 or line ACM

fully into the Austenite range. It is held at this temperature to fully convert the structure into Austenite,

and then removed form the furnace and cooled at room temperature under natural convection. This resultsin a grain structure of fine Pearlite with excess of Ferrite or Cementite. The resulting material is soft; the

degree of softness depends on the actual ambient conditions of cooling. This process is considerably

cheaper than full annealing since there is not the added cost of controlled furnace cooling.

The main difference between full annealing and normalizing is that fully annealed parts are uniform in

softness (and machinablilty) throughout the entire part; since the entire part is exposed to the controlled

furnace cooling. In the case of the normalized part, depending on the part geometry, the cooling is non-

uniform resulting in non-uniform material properties across the part. This may not be desirable if further

machining is desired, since it makes the machining job somewhat unpredictable. In such a case it is better

to do full annealing


13/24

13

y Case hardening

Case hardening produces a hard, wear-resistant surface or case over a strong, tough core. The principal

forms of casehardening are carburizing, cyaniding, and nitriding. Only ferrous metals are case-

hardened. Case hardening is ideal for parts that require a wear-resistant surface and must be tough enough

inter- nally to withstand heavy loading. The steels best suited for case hardening are the low-carbon

and low-alloy series. When high-carbon steels are case-hardened, the hardness penetrates the core and

causes brittleness. In case hardening, you change the surface of the metal chemically by introducing a

high carbide or nitride content. The core remains chemically unaffected. When heat-treated, the

high-carbon surface responds to hardening, and the core toughens.


14/24

14

3.Composite processes

y Wet lay-up

The fibre is positioned in or on the mould by hand. If the mould is a complex shape small pieces of mat

are cut to fit and then more layers applied to achieve the required thickness. The liquid resin is poured

over the fibre and rolled to ensure complete wetting of the fibre and removal of air bubbles. In general the

resin cures at room temperature with the use of an accelerator and a catalyst. If a hot cure is used then

there is no need to use an accelerator. Post curing of cold cured laminates is recommended (2 hours @

80C or 16 hours @ 40C depending on resin manufacturers instructions).

Prior to application of the fibre and resin, the mould is prepared with either polyvinyl alcohol or non-

silicon wax to aid release of the component. Release of the component is achieved by either tapping

wedges between mould and component or by the use of compressed air to gently force the pieces apart.

Chopped Strand Mat is the most commonly used fibre although woven roving is used when a stronger and

stiffer laminate is required. A gel coat is applied to the mould surface to produce a resin rich smooth

surface for appearance and protection purposes. For improved surface finish and corrosion resistance a

surface veil is used which is applied with an embedded fabric for reinforcement or mixed with resin for

smooth surface.


15/24

15

y Prepreq lay-up

y Filament windingFilament winding is a fabrication technique for creating composite material structures. The process

involves winding filaments under varying amounts of tension over a male mould or mandrel. The mandrel

rotates while a carriage moves horizontally, laying down fibers in the desired pattern. The most common

filaments are carbon or glass fiber and are coated with synthetic resin as they are wound. Once the

mandrel is completely covered to the desired thickness, the mandrel is placed in an oven to solidify (set)

the resin. Once the resin has cured, the mandrel is removed, leaving the hollow final product.

Filament winding is well suited to automation, where the tension on the filaments can be carefully

controlled. Filaments that are applied with high tension results in a final product with higher rigidity and

strength; lower tension results in more flexibility. The orientation of the filaments can also be carefully

controlled so that successive layers are plied or oriented differently from the previous layer. The angle at

which the fiber is laid down will determine the properties of the final product. A high angle "hoop" will

provide crush strength, while a lower angle pattern (known as a closed or helical) will provide greater

tensile strength


16/24

16

y Press moldingCompression molding is a method of molding in which the molding material, generally

preheated, is first placed in an open, heated mold cavity. The mold is closed with a top force or

plug member, pressure is applied to force the material into contact with all mold areas, while heatand pressure are maintained until the molding material has cured. The process employs

thermosetting resins in a partially cured stage, either in the form of granules, putty-like masses, or

preforms. Compression molding is a high-volume, high-pressure method suitable for molding

complex, high-strength fiberglass reinforcements. Advanced composite thermoplastics can also

be compression molded with unidirectional tapes, woven fabrics, randomly oriented fiber mat or

chopped strand. The advantage of compression molding is its ability to mold large, fairly intricate

parts. Also, it is one of the lowest cost molding methods compared with other methods such as

transfer molding and injection molding; moreover it wastes relatively little material, giving it anadvantage when working with expensive compounds. However, compression molding often

provides poor product consistency and difficulty in controlling flashing, and it is not suitable for

some types of parts.


17/24

17

y Resin transfer molding(RTM)Resin transfer molding (RTM) is a low pressure closed molding process for moderate volume

production quantities, filling the gap between the slow, contact molding processes and the faster,

compression molding process, which requires higher tooling costs. Continuous strand mats andwoven reinforcement is laid up dry in the bottom mold half. Preformed glass reinforcements are

often used for complex mold shapes. The mold is closed and clamped, and a low viscosity,

catalyzed resin is pumped in, displacing the air through strategically located vents. Metered

mixing equipment is used to control resin/catalyst ratios that are mixed through a

motionless/static mixer and injected into the mold port


18/24

18

y Resin infusion

Resin infusion is an environmentally friendly alternative to open molding. Resin infusion

produces consistent, high-quality parts for products like pleasure boats and windmill blades.Using this process, large and complex structures are produced, and cores and inserts may be

incorporated.

This process impregnates layers of dry reinforcement contained between a rigid, air-tight mold

and a flexible sheet sealed to it around its perimeter. A partial vacuum is applied to the mold

cavity before resin is allowed to infuse into the reinforcement under atmospheric pressure,

impregnating both across and down through the reinforcement layers. The upper sheet is removed

once resin cure is complete, and the component may be removed.


19/24

19

y Chopper gun sprayed materials

Fibreglass spray lay-up process is very different to the hand lay-up process. The difference comes

from the application of the fibre and resin material to the mould. Spray-up is an open-moulding

composites fabrication process where resin and reinforcements are sprayed onto a reusable

mould. The resin and glass may be applied separately or simultaneously "chopped" in a combined

stream from a chopper gun. Workers roll out the spray-up to compact the laminate. Wood, foam,

or other core material may then be added, and a secondary spray-up layer embeds the core

between the laminates. The part is then cured, cooled, and removed from the mould.


20/24

20

Kobe Precision Technology Sdn Bhd.

Plot 39, Phase IV,

Bayan Lepas Industrial Estate,

11900 Penang, Malaysia

KPTec is the leading manufacturer of aluminum substrate in the world. We have the

latest and most advanced manufacturing process, equipment and facility. Aluminum

substrate is the base material for HDD media that uses magnetic recording technology

for its storage. Our key customers are the largest hard disk drive suppliers in the

world. KPTec invests heavily in people and technology to produce consistently high

quality product to cast our position as the leading aluminum substrate supplier for the

HDD industry.

Our process

y Blanky Substrate


21/24

21

Blanking Process

Our Blanking process has been developed to a highly advanced and matured level to

be a leading edge process of the HDD industry. Blanking is a process whereby the

aluminum coil or sheet is stamped into disk form. The disk then goes for heat

treatment to allow recrystallization of the microstructure to occur before final

inspection and testing. Our blanks are mainly for internal use although a portion is

sold to certain customers.


22/24

22

Substrate Process

Substrate process is where the aluminum blanks undergo chamfering, annealing,

grinding and cleaning. The blanks are edge-lathed (chamfered) according to

customer's InnerDiameter & OuterDiameter (IDOD) specifications. The chamfered

blanks are then annealed at a certain temperature for a period of time to release the

mechanical stress from blanking process. Finally, the blanks undergo surface grinding

and cleaning. Grinding is the most critical process, as its purpose is to meet certain

edge profiles or curvatures, surface waviness and roughness. Our substrate facility is

capable to process various form factors and sizes.


23/24

23

Conclusion

In conclusionStudent able to know about manufacturing process,especially heat treatment

method is important to know about flow process,after that student gain about the process

industrial manufacturing,

Beside that student also know about the how to design part effectively with use manufacturing

process,and lastly This knowledge facilitates the students to get a job after graduate will

Bibliography

Serope Kalpakjian,2010,Manufacturing Engineering and Technology,Singapore:Pearson

Education South Asia Pte Ltd

Meyers and Krishan Kumar Chawla,1999, Mechanical Behavior of Materials,United Kingdom:

Cambridge University Press

Vasiliev,2007, Advanced Mechanics of Composite Materials, Department of Mechanics and

Optimization of Processes and Structures, Russian State University of Technology, Moscow,Russia

Avallone, Eugene A.; & Baumeister III, Theodore (1996). Mark's Standard Handbook for

Mechanical Engineers (8th ed.). New York: McGraw-Hill. ISBN 0-07-004997-1

Web

Composites, Copyright 1998-2005 by Pichai Rusmee,http://www.mech.utah.edu

Composites - A Basic Introduction, AZoM.com Pty.Ltd Copyright 2000-2010,http://www.azom.com/

Properties for Composite Materials, AZoM.com Pty.Ltd Copyright 2000-2010,

http://www.azom.com/


24/24

24

material process

Documents

Transcript of material process