‫بسم هللا الرحمن الرحيم‬
‫أساسيات التقنية‬
‫الهندسية‬
‫مقرر رقم ‪101‬‬
Lecture 1: Introduction
Shemy M. Ahhmed
PhD Tohoku university Japan
Professor in Material Engineering

Office:
Mechanical Engineering Department
Office Tel. 1801
 Office Hours:
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Introduction; Properties of materials and their
applications; Workshop metrology; Basic bench work
operations; Machining operations; Tools, equipment and
machinery used in basic workshop processes: turning,
milling, grinding, forging, sheet metal-work; Welding
processes: gas welding, arc welding, brazing and
soldering; Casting processes: sand casting, die casting;
Industrial safety; Function and planning of workshop
.
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Textbook: Singh, R. “Introduction to Basic
Manufacturing Processes and Workshop Technology”,
2006 New Age International (P) Ltd., Publisher
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1st mid term
2nd mid term
Assignments and Projects
Lab Attendance and Notebook
Lecture Attendance and Oral Exam
Final Exam
Total
15%
15%
10%
10%
10%
40%
100%
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Observe the objects around you:
◦ How did they become what they are?
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What important role does manufacturing play
in society?
How do we define manufacturing?
◦ Manufacturing is the ability to make goods and
services to satisfy societal needs
 Manufacturing processes are string together to
create a manufacturing system (MS)
Importance of Course
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All engineers must know the basic
requirements of workshop activities in term
of :
man, machine, material, methods, money and
other infrastructure facilities needed to be
positioned properly for optimal shop layouts
or plant layout and other support services
effectively adjusted or located in the industry
or plant within a well planned manufacturing
organization.
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Primary Shaping Processes
(1) Casting, (2) Powder metallurgy, (3) Plastic technology, (4) Gas cutting, (5)
Bending and (6) Forging
Secondary or Machining Processes
1) Turning, (2) Threading, (3) Knurling, (4) Milling, (5) Drilling, (6) Boring, (7)
Planning, (8) Shaping, (9) Slotting, (10) Sawing, (11) Broaching, (12) Hobbing, (13)
Grinding, (14) Gear cutting, (15) Thread cutting and (16) Unconventional
machining processes namely machining with Numerical Control (NC) machines
tools or Computer Numerical Control (CNC) machines tools
Metal Forming Processes
Hot working Processes
(1) Forging, (2) Rolling, (3) Hot spinning, (4) Extrusion, (5) Hot drawing and (6) Hot
spinning
Cold working processes
(1) Cold forging, (2) Cold rolling, (3) Cold heading, (4) Cold drawing, (5) Wire
drawing, (6) Stretch forming, (7) Sheet metal working processes such as piercing,
punching, lancing, notching, coining, squeezing, deep drawing, bending etc.
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Joining Processes
(1) Welding (plastic or fusion), (2) Brazing, (3) Soldering, (4) Riveting, (5) Screwing, (6)
Press fitting, (7) Sintering, (8) Adhesive bonding, (9) Shrink fitting, (10) Explosive
welding, (11) Diffusion welding, (12) Keys and cotters joints, (13) Coupling and (14) Nut
and bolt joints.
Surface Finishing Processes
(1) Honing, (2) Lapping, (3) Super finishing, (4) Belt grinding, (5) Polishing, (6) Tumbling,
(7) Organic finishes, (8) Sanding, (9) deburring, (10) Electroplating, (11) Buffing, (12)
Metal spraying, (13) Painting
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Processes Effecting Change in Properties
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(1) Annealing, (2) Normalising, (3) Hardening, (4) Case hardening, (5) Flame hardening,
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(6) Tempering, (7) Shot peeing, (8) Grain refining and (9) Age hardening.
Steels
Cast irons
Al-alloys
Metals
Cu-alloys
Ni-alloys
Ti-alloys
PE, PP, PC
PA (Nylon)
Alumina
Si-Carbide
Ceramics,
glasses
Soda-glass
Pyrex
Ceramic foams
Glass foams
Unit 1, Frame 1.4
Butyl rubber
Neoprene
Composites
Polymer foams
Metal foams
Foams
GFRP
CFRP
Polymers,
elastomers
KFRP
Plywood
Woods
Natural
materials
Natural fibres:
Hemp, Flax,
Cotton
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A manufacturing process is a process that
changes the shape or properties of materials.
Hence, materials are the foundation of
manufacturing
In this chapter, we will study the basics of
materials: structure, physical and mechanical
properties, surface, wear and friction, and etc.
The roadmap ahead
An outline of engineering materials ◦
An outline of the behavior and manufacturing ◦
properties of materials
12
13
Main Types of Iron
1. Pig iron
2. Cast iron
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Pig Iron
Pig iron was originated in the early days by reduction or
iron ores in blast furnace and when the total output of the
blast furnace was sand cast into pigs which is a mass of
iron roughly resembling a reclining pig.
The charge in the blast furnace for manufacturing pig iron
is
(a) Ore Consisting of iron oxide or carbonate associated
with earth impurities.
(b) Coke A fuel
(c) Limestone A flux
Cast Iron
Cast iron is basically an alloy of iron and carbon and is obtained by remelting pig iron with coke, limestone and steel scrap in a furnace
known as cupola. The carbon content in cast iron varies from 1.7% to
6.67%. It also contains small amounts of silicon, manganese,
phosphorus and sulphur in form of impurities elements.
General properties of cast iron
Cast iron is very brittle and weak in tension and therefore it cannot be
used for making bolts and machine parts which are liable to tension.
Since the cast iron is a brittle material and therefore, it cannot be used
in those parts of machines which are subjected to shocks. It has low
cost, good casting characteristics, high compressive strength, high wear
resistance and excellent machinability. These properties make it a
valuable material for engineering purposes.
Cast Iron
Cast iron is basically an alloy of iron and carbon and is obtained by remelting pig iron with coke, limestone and steel scrap in a furnace
known as cupola. The carbon content in cast iron varies from 1.7% to
6.67%. It also contains small amounts of silicon, manganese,
phosphorus and sulphur in form of impurities elements.
General properties of cast iron
Cast iron is very brittle and weak in tension and therefore it cannot be
used for making bolts and machine parts which are liable to tension.
Since the cast iron is a brittle material and therefore, it cannot be used
in those parts of machines which are subjected to shocks. It has low
cost, good casting characteristics, high compressive strength, high wear
resistance and excellent machinability. These properties make it a
valuable material for engineering purposes.
Steels
Steel is an alloy of iron and carbon with carbon content
maximum up to 1.7%. The carbon occurs in the form of iron
carbide, because of its ability to increase the hardness and
strength of the steel. The effect of carbon on properties of steel
is given in Figure 1. Other elements e.g. silicon, sulphur,
phosphorus and manganese are also present to greater or lesser
amount to import certain desired properties to it. Most of the
steel produced now-a-days is plain carbon steel. Carbon steel
has its properties mainly due to carbon content and does not
contain more than 0.5% of silicon and 1.5% of manganese.
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Alloy steel
For improving the properties of ordinary steel, certain alloying
elements are added in it in sufficient amounts. The most
common alloying elements added to steel are chromium, nickel,
manganese,
silicon,
vanadium,
molybdenum,
tungsten,
phosphorus, copper, that the titanium, zirconium, cobalt,
columbium, and aluminium. Each of these elements induces
certain qualities in steels to which it is added. They may be used
separately or in combination to produce desired characteristics in
the steel. The main purpose of alloying element in steel is to
improve machinability, elasticity, hardness, case hardening,
cutting ability, toughness, wear resistance, tensile strength,
corrosion resistance, and ability to retain shape at high
temperature, ability to resist distortion at elevated temperature
and to impart a fine grain size to steel.
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Fig. 1 Effect of carbon on properties of steel
Non-ferrous materials
Non-ferrous metals contain metals other than iron as their main
constituents such as aluminum, copper, zinc, magnesium, lead,
tin, nickel and their alloys and non-metallic materials. Various
non-ferrous alloys are copper base (brass, bronze), aluminum
base alloys (duralumin, …) nickel alloys (inconel, monel,..), tin
base alloys(bearing or antifriction alloys). The non-ferrous metals
are used for the following purposes namely resistance to
corrosion, special electric and magnetic properties, softness,
facility of cold working, ease of casting, good formability, low
density and attractive color
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Properties are defined as
what matter is like and
how it behaves.
Properties are divided
into two major groups:
chemical and physical.
Physical properties are those that
describe what the matter is like
(what does it look like, feel like,
taste like, etc.). They are those
properties that can be observed
with our senses.
Color
Size
Shape
Density
State of matter
Odor
Texture
Chemical properties describe how matter
behaves (what does it do when one type of
matter encounters or reacts with another.
Those properties can only be observed when
matter reacts or doesn’t react.
Rusting
Chemical reactivity
Flammability
Combustibility
Mechanical properties
General
Thermal expansion
Cost/kg Cm, $/kg Expense:
Mechanical
Young’s modulus E, GPaStiffness:
Elastic limit,y
Young’s modulus, E
Strain 
Stress 
Brittle materials
Tensile (fracture)
strength,
ts

Young’s
modulus, E
Strain 
Elastic limit y , MPa Strength:
o

Expansion
coefficient, 
Temperature, T
Fracture strength: Tensile strength ts ,
MPa
Thermal conduction
x
Fracture toughness
Brittleness:
To
T1
Kic , MPa.m1/2
Thermal
Expansion: Expansion coeff. , 1/K
Conduction: Thermal conductivity ,
W/m.K
Electrical
Conductor? Insulator?
Area A
Heat flux, Q/A
Stress 
Ductile materials
Thermal strain

Density , Mg/m3Weight:
Q
joules/sec
Thermal
conductivity, 
(T1 -T0)/x
Example of Applications
Metals and Alloys
Gray cast iron
Ceramics and 
Glasses 
 SiO2-Na2O-CaO
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Polymers
Polyethylene
Properties
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Automobile engine blocks
Castable, machinable,
vibration damping
Window glass
Optically transparent,
thermally insulating
Food packaging
Easily formed into
thin flexible, airtight
film
Example of Applications
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Properties
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Semiconductors
Silicon
Transistors and integrated Unique electrical
circuits
behavior
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Composites
Tungsten carbide
resistance
-cobalt (WC-Co)
Carbide cutting tools for
machining
High hardness, yet
good shock
The atomic structure of materials
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Materials are made of elements ◦
The atomic structure of the elements ◦
The periodic table of elements at Los Alamos ◦
National Laboratory:
http://pearl1.lanl.gov/periodic/default.htm
e
e
e
e
e
Neon
e
e
e
+
e
e
Electrons
Nucleus
Max No. of electrons = 2n2
30
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The bonds between atoms and molecules
◦ Primary bonds: atom-to-atom bonding
◦ Secondary bonds: molecules attract each other
Inter-molecular attract Temporary attract
Atom attract
31
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The structure of engineering materials:
◦ Crystalline: most solids
◦ Non-crystalline: most liquids and gases
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Crystalline structures
◦ A typical crystalline structure
Body-Centered
Cubic (BCC)
unit cell
The model
of BCC
A practical BCC
material
32
The types of crystalline structures
BCC: Body Centered Cubic is stable and hence, is hard
FCC: Face Centered Cubic is easy to slide and hence, is soft
HCP: Hexagonal Close-Packed is very stable
Materials may change their structure under
different temperature (e.g., water)
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Crystalline structures of common metals
BCC: Iron (Fe), Tungsten (W), …
FCC: Aluminum (Al), Copper (Cu), Gold (Au), ..
HCP: Magnesium (Mg), Titanium (Ti), …
Crystalline structures may be imperfect
34
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Crystalline structure deformation
◦ Crystalline structure may deform under stress
Elastic
deformation
Plastic
deformation
◦ Types of deformation:
 Elastic deformation: the lattice structure tiltes resulting
temporary change of shape
 Plastic deformation: the lattice structure changes
resulting in permanent change of shape
35
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Non-crystalline (Amorphous) structure
◦ A comparison
 Crystalline structure: regular, repeating and densely
packed
 Non-crystalline structure: random and loosely packed
Crystalline
Non-crystalline
◦ Although many non-crystalline materials are
liquid and gas, there are solid non-crystalline
materials such as glass, some plastics and
rubber
36
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Non-crystalline structure (continue)
◦ Non-crystalline structures may mix to crystalline
structures within one material
◦ Materials may change its structure under
different temperature
Melting temperature
Glass-transition temperature
37
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Grains and grain boundaries
◦ Individual crystals are called grains.
◦ Materials are made of many randomly oriented
crystals
38
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Grains and grain boundaries (continue)
◦ Grain size effects the materials properties
 Large grain → low strength, low hardness, low ductility
and rough surface
◦ Grain size
 The formula:
N = 2n-1
where, n is the ASTM grain size number and N is the number of
grains per square inch at a magnification of 100 (0.0645 mm2).
 Examples:
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n = - 3, N = 1 grains/mm2, 0.7 grains / mm3,
n = 0, N = 8 grains/mm2, 16 grains / mm3,
n = 3, N = 64 grains/mm2, 360 grains / mm3,
…
◦ Grain boundary has a more complicated effect
39
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Structures under plastic deformation
◦ If a materials undergoes a plastic deformation,
it will become anisotropic
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Structures
under plastic deformation (continue)
◦ The effect of the temperature: recovery,
recrystallization and grain growth
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Structures of engineering materials
◦ Metals:
 Crystalline structure: BCC, FCC or HCP
 Primary bonding (metallic bonding)
◦ Polymers:
 Mostly non-crystalline structures
 Large molecules with secondary bonding (intermolecular bonding)
◦ Ceramics:
 Either crystalline or non-crystalline structures
 Primary bonding (ionic or covalent or both) and
secondary bonding (atom attraction force)
42
The structure determines the property
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Modeling the structure is extremely
difficult if not impossible
A piece of metal
Crystal structures
Grain structures
43
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Material properties
◦ Mechanical properties
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Stress-strain
Hardness
Fatigue and Creep
Fluid property
Viscosity
◦ Physical properties
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Quantitative measures of
material
Volumetric property
Thermal property
Mass diffusion
Electronic property
Electrochemical property
44
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Mechanical property 1: stress-strain
◦ Types of stress
 Tensile stress: stretch
 Compression stress: squeeze
 Shear stress: tear apart
Most common
◦ Stress testing
45
◦ Stress calculation
 The formula
F
e 
A0
 Note:
 e = engineering stress, PSI or MPa
 F = applied force, lb or N
 A0 = original area of the specimen, in2 or mm2
◦ Strain calculation
 The formula:
L  L0
L0
 Note: it has no unit
e
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◦ Reduction of area
Reduction of area 
A0  A
100
A0
◦ Typical strain-stress graph
Stress (e)
Tensile stress
TS
Y
Maximum load
Necking
Plastic deformation
Yield stress
Elastic deformation
Strain (e)
47
◦ The process of stress-strain testing
Plastic deformation
Necking
Stress (e)
Breaking
Elastic
deformation
Strain ()
48
◦ The relationship between the stress and strain in
the elastic deformation zone
 The specimen will return to original shape after the force
is removed
 The formula (the Hooke’s law)
e = Ee
where, E = modulus of elasticity, or Young’s module
◦ The relationship between the stress and strain in
the plastic deformation zone
 The specimen will not return to the original shape after
the force is removed
 Necking is when localized material deformation occurs.
 It will be detailed later.
49
◦ An example
 The experiment setup
 The testing data on an aluminum alloy specimen
Yield stress: 22 ksi
Tensile stress: 35 ksi
Young’s module: 7x104 MPa
50
◦ The stress and strain properties of selected
engineering materials
Material
Al and alloys
Case iron
Copper alloys
Steel (low C)
Steel (high C)
Titanium
Concrete
Silicon carbide
Diamond
Polyethylene
Nylon
E (MPa)
69 x 103
138 x 103
16 x 103
209 x 103
209 x 103
117 x 103
48 x 103
448 x 103
1035 x 103
7.0 x 103
3.0 x 103
Y (MPa)
175
275
205
175
400
800
UTS (MPa)
350
275
410
300
600
900
51
◦ Other important measures
 Total elongation
EL 
L f  L0
L0
ductility
 Total area reduction
AR 
A0  A f
A0
 The specific (per volume) work to fracture the material

Ws   d
toughness
0
52
◦ True strain-stress
 The problem of engineering strain-stress
 True stress
F

A
 True strain
Actual (instantaneous) area
dL
L
 ln
L0 L
L0
 The difference to the stress-strain:
the plastic deformation is more

clearly shown
 
L
Y
Plastic deformation
Elastic deformation

53
◦ True stress-strain (continue)
 The correlation to the engineering stress-strain
 = ln(1 + e)
Engineering strain
 = e(1 + e)
Engineering stress

54
◦ Strain hardening
 From the figure, it is seen that after exceeding the tensile
strength, the material will require less force to deform
 In practice, however, we know that the larger the
deformation, the larger the force. This is called strain
hardening
 The interpretation lays on
the strain hardening: the
Projected curve
if no necking
size of the material has
changed. In fact, if the size

does not change, then the
required force will continue
Plastic deformation
to increase
Elastic deformation

55
◦ The flow curve equation (applicable to the plastic
region):
 = Kn
where, K is the strength coefficient or flow strength
(MPa) and is equal to the true stress at a true strain
of unity, and n is the strain hardening exponent and
is equal to the true strain at the onset of necking.
◦ Another form:
log = logK + nlog
◦ Two important formulas
=n
n = a/b
56
◦ Application examples
 Example 1: strain hardening and stamping operation –
Larger forces are needed after initial metal deformation
 Example 2: the large the n, the more difficult it is to break
(necking). For instance, steel (n = 0.4) is more difficult to
break than the aluminum (n = 0.15)
◦ The types of stress-strain relationship
Perfect elastic
Perfect plastic Elastic and strain hardening
57
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Compression test
◦ How to test the compression stress-strain
◦ The formula
e 
e
F
A0
h  h0
h0
◦ A comparison to tensile stress-strain: much more
load is required in the plastic region because:
 The size increases
 The friction increases (barreling effect)
58
◦ Illustration of the barreling effect
Friction
prevents the
material to
move
59
 A typical compression curve
 The elastic deformation zone is about the same
 The plastic deformation requires more force
 The engineering compression stress-strain and true
compression stress-strain are almost the same
 Question: when does a specimen fail?

Y
Plastic deformation
Elastic deformation

60
◦ Shearing (Torsion)
 Shearing is to apply stresses in opposite directions of a
specimen
F
b
F
d
A
F
F
 The shearFstress and
d strain
g 
t
b
A
where, t = shear stress (MPa), F = applied force (N), A =
area over which the force is applied (mm2), g = shear strain
(no unit), d = deflection of the element, and b =
orthogonal distance over which deflection occurs (mm).
61
 Shearing test setup
 Stress and strain
T
t
2R 2t
R
g 
L
 Typical shear curves
 The relationship in the
elastic region
t = Gg
Shear modulus, G  0.4E
62
◦ Bending and testing of brittle materials
 The setup
 The transverse rupture strength
1.5 FL
TRS 
bt 2
where, TRS = transverse rupture strength (MPa), F =
applied force (N), L = length of the specimen between
supports (mm); and b and t are the dimensions of the
cross section (mm).
63

Mechanical property 2: Hardness
◦ Definition of hardness: the resistance to
permanent indentation
◦ Hardness tests
64
◦ Brinell test
 Use a carbide ball of 10 mm diameter to press the surface
of a specimen
 The applied force is 500, 1,500 or 3,000 kg.
 The formula to compute the HB value:
HB 
2F
Db Db 
Db2  Di2

 An empirical relationship with the ultimate tensile stress
for steel:
UTS (N / mm2) = 3.5 HB (N / mm2)
Indentation must be fully
developed in the test
65
◦ Rockwell test
 Use a cone-shaped indenter to press the specimen
 The applied force is first 10 kg (minor force) and then
150 kg (major force)
 The additional depth of indentation is the hardness
 The Rockwell scales
Scale
Symbol
Indenter
Specimen
A HRA
Cone
60
B HRB
(1/16)” ball
100
C HRC
Cone
150
Load
carbide
aluminum
steel
66
◦ Vickers test
 Use a pyramid-shaped indenter made of diamond to
press the specimen
 The formula
1.854 F
HV 
D2
◦ The relationship of different hardness scales
◦ The hardness of various materials: check
www.matweb.com
67
◦ A list of
commonly
used
material
hardness
68
◦ The effect of the temperature
 The strength decreases when the
temperature increases
 The ductility increases when the
temperature increases
 The hardness decreases when the
temperature increase
69

Material property 3: Fatigue and Creep
◦ Fatigue: material strength decreases under
constant loading
◦ Creep: material elongates under constant loading
Fatigue examples
Creep examples
70

Material property 4: Fluid property
◦ Viscosity
 Definition: the resistance to flow
 Measuring the viscosity
Viscosity  
Shear stress t  F
t
g
A
Rate of shear g 
dv
dy
71
◦ Viscosity values of selected fluids
Material
Water at 20 oC
Water at 100 oC
Mercury at 20 oC
Machine oil at 20 oC
Pancake syrup at 20 oC
Polymer at 151 oC
Polymer at 205 oC
Polymer at 260 oC
Glass at 540 oC
Glass at 815 oC
Glass at 1095 oC
Glass at 1370 oC
viscosity  (N-s /m2 or Pas)
0.001
0.0003
0.0016
0.1
50
115
55
28
1012
105
103
15
72
◦ Viscoelastic
 Viscoelastic = viscosity at elastic state
 Owing to the effect of viscosity, the material (such as
polymer) may not return to its original shape after the
elastic deformation immediately. Instead, it returns to its
original shape gradually.
 An example: bread dough
 The relationship between strain and stress of a
viscoelastic material:
(t) = f(t)
Elastic
f(t)
Viscoelastic
The modulus of viscoelastic
Rubbery
Viscous flow
t (temperature)
73

Physical property 1: volumetric and
melting properties
◦ Density (): the weight per unit volume in
(g/cm3)
◦ Thermal expansion coefficient (): the change
in length per degree of temperature increase
in (oC-1)
◦ Melting point: the temperature at which the
material changes from solid to liquid
◦ The properties of typical materials
74
~ 1600 oC
75

Physical Property 2: thermal properties
◦ Specific heat (C): the quantity of heat energy
required to increase the temperature of a unit
mass of the material by 1 degree, in (Cal/g-oC).
◦ Thermal conductivity (k): the capability to transfer
heat, in (J/sec-mm-oC).
◦ An example: computing the required amount of
heat to melt 1,000 g of steel (W):
 The formula:
H = CW(T2 – T1)
 Hence,
(0.11)(1000)(1600 – 20) = 173800 Cal
= 0.2022 KW-hour
76
It is
temperature
dependent!
77

Physical Property 3: electrical properties
◦ Resistivity:
 How to compute the resistance:
R
L
A
where, L is the length, A is the area, and  is the resistivity
of the material.
 Resistivity is a measure of conductivity
◦ The electric conductivity:
 The formula
EC 
1

Note that the unit is (-m)-1.
78
◦ The resistivity of selected materials
Material
Conductors
Steel
Aluminum
Copper
Silver
Semiconductors
Silicon
Resistivity ((-m)-1)
10-6 ~ 10-8
17.0 × 10-8
2.8 × 10-8
1.7 × 10-8
Note that the
1.6 × 10-8
resistivity is also a
function of
1
5
10 ~ 10
temperature
1.0 × 103
Insulators
Rubber
polyethylene
1012 ~ 1015
1.0 × 1012
100 × 1012
79











The term bench work denotes the production of an article by hand
on the bench. Where as fitting is the assembling of parts together
and removing metals to secure the necessary fit, and may or may
not be carried out at the bench.
TOOLS USED IN FITTING SHOP
1.
2.
3.
4.
5.
6.
7.
8.
9.
Marking tools
Measuring devices
Measuring instruments
Supporting tools
Holding tools
Striking tools
Cutting tools
Tightening tools, and
Miscellaneous tools
Steel Rule
Circumference Rule
Straight Edges
scribers
Bevel Protractor
Prick Punch
Surface Gauge or Scribing Block

Universal Surface Gauge



Fillet and
Radius Gauge
A use of fillet
and radius
gauge
Screw Pitch
Gauge
Surface Plate
A use of surface plate and vblock
OUTSIDE MICROMETER
Outside Micrometer
Inside Micrometer
Depth Micrometer
7.38 mm
7.72mm
A simple outside
caliper
A caliper held in
rule
A standard spring
joint outside caliper
Calipers ‫البراجل‬
Calipers ‫البراجل‬
‫قياس الزوايا‬
‫‪ The Try square‬الزاوية القائمة‬
‫ المنقلة‬Plain Protractor
‫ المنقلة ذات الورنية‬Vernier Protractor
Vernier Protractor ‫المنقلة ذات الورنية‬
‫ المنقلة ذات الورنية‬Vernier Protractor
The reading is 46° - 20‘
Exp.4 : Angle Measurements
26/09/1437

10
2
A bench vice
Files
Classification of Files
Types of files according to cuts of teeth
General
classification
of files based on
Shapes or cross
sections
Scrapers
Common types of scraper
Chisel
Flat Chisel
Cross cut Chisel
Half round nose Chisel
Rake
angle
Clearance
angle
Diamond point chisel
Web Chisel
Cutting angle
Drill
A bench drilling machine
Types of hand drilling machine
TAPS
Nomenclature of tap
Types of hand taps
Hand hacksaw
A fixed frame hacksaw
An adjustable frame hacksaw
Pliers
Screw driver
Introduction
Casting processes
Metal Solidification
Fluid Flow
Fluidity of Molten Metal
Heat Transfer
Casting Defects
Introduction
Casting process is one of the earliest metal shaping
techniques known to human being. It means pouring
molten metal into a refractory mold cavity and allows it
to solidify. The solidified object is taken out from the
mold either by breaking or taking the mold apart. The
solidified object is called casting and the technique
followed in method is known as casting process.
Casting technology involves the next steps:
Examples of Cast Parts
A large sand casting weighing over 680 kg (1500 lb) for an
air compressor frame (photo courtesy of Elkhart Foundry).
Engine Block
C-clamps formed by casting (left) and machining (right)
Casting process
Casting Processes
Metals processed by casting
• Sand casting – 60%
• Investment casting – 7%
• Die casting – 9%
• Permanent mold casting – 11%
• Centrifugal casting – 7%
• Shell mold casting – 6%
Cupola furnace
Furnaces
Induction Furnace
Electric Furnace
Casting Terminology
Flask
The box containing the mold
Cope
The top half of any part of a 2-part mold
Drag
The bottom half of any part of a 2-part mold
Core
A shape inserted into the mold to form internal cavities
Core Print
A region used to support the core
Mold Cavity
The hollow mold area in which metal solidifies into the part
Riser
An extra cavity to store additional metal to prevent
shrinkage
Gating System
Channels used to deliver metal into the mold cavity
Pouring Cup
The part of the gating system that receives poured metal
Sprue
Vertical channel
Runners
Horizontal channels
Casting Design
Schematic illustration of a typical riser-gated casting. Risers
serve as reservoirs, supplying molten metal to the casting as it
shrinks during solidification
Sand Casting
Taper on patterns for ease of removal from the sand mold
Production Steps in Sand-Casting
Outline of production steps in a typical sand-casting operation.
Solidification of Pure Metals
A pure metal solidifies at a constant temperature
equal to its freezing point (same as melting point)
Investment casting (lost wax casting)
Steps in investment casting
• Wax patters are produced
• Several patterns are attached to a sprue to form a
pattern tree
• The pattern tree is coated with a thin layer of
refractory material
• The full mold is formed by covering the coated tree
with sufficient refractory material to make it rigid
• The mold is held in an inverted position and heated
to melt the wax and permit it to drip out of the cavity
• The mold is preheated to a high temperature, what
insures that all the contamination are eliminated from
the mold: it is also permits the liquid metal to flow more
easily into the detailed cavity; the molten metal is
poured; it solidifies and
• The mold is broken away from the finished casting.
Parts are separated from sprue
Steps in permanent mold casting: (1) mold is
preheated and coated
Steps in permanent mold casting: (2) cores (if used) are
inserted and mold is closed, (3) molten metal is poured
into the mold, where it solidifies.
A permanent mold casting process in which
molten metal is injected into mold cavity
under high pressure
 Pressure is maintained during solidification,
then mold is opened and part is removed
 Molds in this casting operation are called
dies; hence the name die casting
 Use of high pressure to force metal into die
cavity is what distinguishes this from other
permanent mold processes


Designed to hold and accurately
close two mold halves and keep
them closed while liquid metal is
forced into cavity
Two main types:
◦
◦
Hot-chamber machine
Cold-chamber machine
Metal is melted in a container, and a piston
injects liquid metal under high pressure into
the die
 High production rates - 500 parts per hour
not uncommon
 Applications limited to low melting-point
metals that do not chemically attack plunger
and other mechanical components
 Casting metals: zinc, tin, lead, and
magnesium
Cycle in hot-chamber casting: (1) with die closed and
plunger withdrawn, molten metal flows into the chamber
Molten metal is poured into unheated
chamber from external melting
container, and a piston injects metal
under high pressure into die cavity
 High production but not usually as fast
as hot chamber machines because of
pouring step
 Casting metals: aluminum, brass, and
magnesium alloys
 Advantages of hot-chamber process
favor its use on low melting-point alloys
(zinc, tin, lead)
Manufacturing
Processes
Deformation
Extrusion
Forging
Rolling
Bar drawing
Wire drawing
Casting
Centrifugal
Die casting
Investment
Permanent mold
Sand casting
Sheet
Metal
Bending
Blanking
Drawing
Punching
Shearing
Spinning
Polymer
Processes
Blow molding
Casting
Compression molding
Extrusion
Injection Molding
Thermoforming
Transfer molding
Machining
Boring
Drilling
Facing
Grinding
Milling
Planing
Turning
Sawing
ECM, EDM
Finishing
Anodizing
Honing
Painting
Plating
Polishing
Assembly
Automated
Bonding
Brazing
Manual
Riveting
Soldering
Welding
Rolling
 Extrusion
 Drawing
 Forging




Forging: Method of forming hot metal by
squeezing between heat-resistant dies.
Open-Die Forging: A large press squeezes (not
strikes) steel between two heat-resisting
surfaces…can be used to shape very large steel
ingots (the ingot may weigh several hundred tons,
the forge can squeeze with a force of several
thousand tons)
Closed-Die Forging: A large hammer pounds the
steel between two heat-resisting shaped dies until
the product is in the desired shape
Hand forging tools
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
Open-Die Drop Hammer - Steam Hammer

Upset forging
◦ Grip a bar—heat the end—forge into desired shape
 Product examples
 Bolts
 Engine valves
Heading
an upsetting process used to create head
bolts, screws or other fasteners.
Impression Die Drop Hammer Forging
Impression drop-forging dies and the
product resulting from each impression.
The flash is trimmed from the finished
connecting rod in a separate trimming die.
The sectional view shows the grain flow
resulting from the forging process
EML 4930/5930
Advanced Materials
In direct extrusion, ram
pushes the billet through
the die. High friction
forces.
In indirect extrusion, ram is
hollow and metal flows through
the ram. Here the friction forces
are low.
There is size limitation
In impact extrusion,
collapsible tooth paste
tubes are used to sheath
cables.
This method is restricted
to softer metals such as
tin, aluminum and
copper.
Tubing can be extruded to close tolerances. There
is a mandrel and it pierces the billet
Rollers in compression
thick
slab
thin
sheet
Plastic deformation
Mannesman Mill.
Plug rolling Mill.
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
‫يعتبر اسلوب السحب العميق من أهم عمليات التشكيل اللدن حيث أنه يتم‬
‫تشكيل األوعية األسطوانية و المستطيلة بهذه الطريقة‪.‬‬
‫‪© 2009 Dr. Eng. Mahmoud El-Sharief‬‬
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief
Sequence of punching: 1. Punch, 2. Sheet, 3. Support
© 2009 Dr. Eng. Mahmoud El-Sharief
‫طرق وصل املعادن‬
Methods of joint
metallic's
‫تتكون أغلبية المنتجات من عناصر أو أجزاء و يلزم‬
‫تجميع هذه األجزاء فى المجمع النهائى طبقا للتصميم‬
‫الموضوع و يتم توصيل هذه األجزاء ببعضها‬
‫البعض بطريقتين ‪:‬‬
‫‪ ‬التوصيل الدائم‪.‬‬
‫‪ ‬التوصيل المؤقت‪.‬‬
‫يقصد بالتوصيل الدائم توصيل األجزاء ببعضها‬
‫توصيال ايجابيا ال ينتظر معه حل هذا االتصال‬
‫مثل‪:‬‬
‫‪ ‬التوصيل بالبرشمة ‪Riveting‬‬
‫‪Welding‬‬
‫‪ ‬التوصيل بالحام‬
‫‪Interference fit‬‬
‫‪ ‬التوصيل المزوجة‬
‫طرق التوصيل الدائم‬
‫هو توصيل يمكن معه معاودة فك الوصالت و تركيبها‬
‫دون اإلخالل بسالمة األجزاء مثل‪:‬‬
‫‪ ‬الوصالت الملولبة ‪Threaded Connection‬‬
‫‪‬‬
‫وصالت الخوابير‬
‫‪Keyed Connection‬‬
‫‪‬‬
‫الوصالت البروز‬
‫‪Spline Connection‬‬
4
4
1
2
3
5
4
‫طريقة حديثة لوصل المعادن بعضها لبعض عن طريق استعمال طاقة حرارية و‬
‫تسليط ضغط علي الجزئين الجارى وصلهما‪ ،‬أو بدون تسليط أى ضغط على‬
‫اإلطالق وال بد من توافر الشروط األتية لتمام عملية اللحام على الوجه األكمل‪:‬‬
‫‪‬تنظيف السطوح‬
‫‪‬تلين سطوح الجزئين بالتسخين لتقارب السطوح‬
‫‪‬منع حدوث أى طبقات داخلية من غير المواد األصلية كاألكاسيد عن طريق‬
‫استخدام مساعدات اللحام‬
‫‪Electric Arc Welding‬‬
‫(‪ )1‬لحام القوس الكهربى‬
‫و فيه تتولد الطاقة الحرارية المستعملة فى عملية اللحام بواسطة قوس كهربى‬
‫يبعث من الجسم الجارى لحامه و قطب اخر (أ)‪ .‬و يستعمل فى هذه‬
‫الطريقة اما أقطاب كربونية أو أقطاب معدنية وهذه األقطاب الكربونية ال‬
‫تعدو كونها طرفا فى قوس يبعث حرارة‪ .‬أما األقطاب المعدنية فانه يؤدى‬
‫الى صهرها و بالتالى إضافتها الى المعدن األساسى بعكس األقطاب‬
‫الكربونية التى يلزم استعمال سلك معدنى منفصل يجرى صهره بالطاقة‬
‫الحرارية المنبعثة من القوس‪.‬‬
Cylinder heads that
are cracked, pitted
or damaged in
other way that
machining cannot
fix then it is on to
fusion welding and
re-casting.
‫‪ ‬لحام القوس الكهربى‬
‫‪Electric Arc Welding‬‬
‫يكون مصدر الطاقة الحرارية لصهر المعادن‬
‫هو القوس الكهربى و يكون التيار الكهربى‬
‫المار فيه عالى الشدة منخفض الجهد‬
‫و تصل درجة الحرارة الى ‪ 3800‬درجة مئوية‪.‬‬
‫لحام القوس الكهربى المعدنى‪ .‬فيه‬
‫يتولد القوس الكهربى بين سلك‬
‫مستنفذ من المادة المالئة (ألكترود)‬
‫المغطى بمادة مساعدة و الشغلة و‬
‫فى هذا اللحام يتولد منطقة غازية‬
‫حامية لمنطقة اللحام وناتجة من تبخر‬
‫المادة المساعدة‪.‬‬
‫لحام القوس الكهربى الغازى (غاز‬
‫خامل)‪ .‬فيه يتولد القوس الكهربى بين‬
‫سلك مستنفذ من المادة المالئة‬
‫(ألكترود) و الشغلة و يتم فى هذا‬
‫اللحام حجب المعدن المنصهر فى‬
‫منطقة اللحام عن طبقة الهواء المحيط‬
‫بالقوس الكهربى عن طريق استخدام‬
‫غاز خامل‪.‬‬
‫لحام القوس الكهربى الغازى باستخدام قطب من‬
‫التنجستين‪ .‬فيه يتولد القوس الكهربى بين سلك غير‬
‫مستنفذ من التنجستين (ألكترود) و الشغلة و يتم فى‬
‫هذا اللحام اإلمداد بغاز لحماية المنطقة المنصهرة‬
‫عن الهواء الخارجى و كذلك يجب اإلمداد بتيار‬
‫كهربى ثابت‪.‬‬
‫لحام القوس الكهربى المغمور و فيه يتم الحصول‬
‫على حرارة عن طريق القوس الكهربى المتولد‬
‫بين مادة مالئة مستنفذة (ألكترود) و الشغلة و يتم‬
‫فى هذا اللحام حجب المنطقة المنصهرة عن الهواء‬
‫الخارجى عن طريق التغطية بحبيبات المادة‬
‫المساعدة‪.‬‬
‫لحام القوس الكهربى بالبالزما وفيه يستخدم‬
‫القوس الكهربى المغلف بين قطب غير‬
‫مستنفذ (ألكترود) و جسم الشغلة وهذا‬
‫القوس الكهربى يحول الغاز الخامل الى‬
‫بالزما التى تستخدم لصهر كل من الشغلة‬
‫و المادة المالئة‪.‬‬
‫لحام شعاع اليزر و فيه يتم انصهار‬
‫المواد تحت حرارة يتم الحصول عليها‬
‫من شعاع دقيق من اليزر و ال يتم‬
‫استخدام مادة مالئة فى هذا الحام‪.‬‬
‫و فيه يستخدم حراق (بورى) لحرق غاز من غازات الوقود كاألسيتيلين أو‬
‫األكسجين الخالص (غير مخلوط بالنتروجين)‪ .‬وذلك لبعث طاقة حرارية‬
‫الزمة لصهر المعدن األساسى و كذلك معدن سيخ الملئ و تصل درجة‬
‫الحرارة تقريبا ‪ 2000‬درجة مئوية‪.‬‬
‫أشكال اللهب للحام األكسى أسيتيلين‪:‬‬
‫لهب مؤكسد‪ :‬تكون به نسبة األكسيجين عالية‬
‫و يستخدم فى لحام النحاس و البرنز (اللهب‬
‫قصيرالطول و شاحب اللون)‪.‬‬
‫لهب متعادل‪ :‬به كميات متسوية من األكسجين‬
‫و اإلسيتيلين و يستخدم فى لحام الصلب‬
‫بأنواعه و الحديد الزهر و النحاس األحمر و‬
‫األلومنيوم (اللهب متوسط الطول و شاحب‬
‫اللون)‪.‬‬
‫لهب مكربن‪ :‬و به نسبة إسيتيلين قليلة ذائدة و‬
‫يمكن استخدامه فى المعادن السبق استخدامها‬
‫مع الهب المتعادل (اللهب طويل و لونه أبيض‬
‫مصفر و المع)‪.‬‬
‫أشكال اللهب للحام األكسى أسيتيلين‪:‬‬
‫لهب مكربن‪ :‬و به نسبة إسيتيلين ذائدة قليلة و‬
‫يمكن استخدامه فى لحام الصلب بأنواعه و‬
‫الحديد الزهر و النحاس األحمر و األلومنيوم‬
‫نفسها مع الهب المتعادل (اللهب طويل و لونه‬
‫أبيض مصفر و المع)‪.‬‬
‫لهب متعادل‪ :‬به كميات متسوية من األكسجين‬
‫و اإلسيتيلين و يستخدم فى لحام الصلب‬
‫بأنواعه و الحديد الزهر و النحاس األحمر و‬
‫األلومنيوم (اللهب متوسط الطول و شاحب‬
‫اللون)‪.‬‬
‫لهب مؤكسد‪ :‬تكون به نسبة األكسيجين عالية‬
‫و يستخدم فى لحام النحاس و البرنز (اللهب‬
‫قصيرالطول و شاحب اللون)‪.‬‬
‫طرق اللحام باألكسى أسيتيلين‪:‬‬
‫اللحام اليمينى‪ :‬تستخدم فى لحام ألواح الصلب‬
‫التى تزيد تخانتها عن ‪ 4.5‬مم‪ ،‬ويسير اللحام فى‬
‫اتجاه الجانب األيمن‪.‬‬
‫اللحام اليسارى‪ :‬يستخدم فى لحام الحديد الزهر‬
‫و المعادن غير الحديدية حيث تتقدم عملية اللحام‬
‫فى اتجاه الجانب األيسر‪.‬‬
‫وفى كلتا الحالتين يعطى سيخ اللحام حركة‬
‫جانبية طفيفة بجانب حركته الطولية و يقصد‬
‫األحتفاظ بجانبى المعدن فى حالة صهر بالمعدن‬
‫المطلوب فى الوقت الذى يجب فيه قصر حركة‬
‫الحراق (البورى) على اتجاه الطولى‪.‬‬
‫و هذا و يمكن استعمال اللهب فى عملية قطع‬
‫المعادن عن طريق استخدام ثالث أنابيب‬
‫(اكسجين‪ ،‬أسيتيلين‪ ،‬اكسجين زائد)‬
‫يعتمد هذا النوع على التفاعل الكيميائى بين األلومنيوم و أكسيد الحديد‬
‫(الثرميت) وتجرى هذه الطريقة بإعداد الجزئين المراد وصلهما على استقامة‬
‫بعضهما و يبنى قالب حول األطراف و يجهز القالب بفتحة سكب إلستقبال‬
‫الصلب المصهور و يوضع الثرميت فى بوتقة ذات فتحة خروج عند قاعها‪ ،‬و‬
‫بإشعال الخليط يحدث التفاعل و ينتج عنه حرارة كبيرة و يتحد األلومنيوم مع‬
‫األكسجين الموجود فى أكسيد الحديد تاركا الصلب الصهور الذى ينساب من‬
‫فتحة قاع البوتقة الى القالب ليقوم بعملية اللحام ‪.‬‬
‫و هو أقدم أنواع اللحام على اإلطالق‪ ،‬و كان يمارس لمدة قرون و فيه يستخدم‬
‫كور الحدادة لتسخين األجزاء المطلوب توصيلها إلى درجة حرارة الطرق‪ ،‬ثم‬
‫تغطى األسطح بمساعد تالحم ( مثل البوراكس) و يعاد تسخينها لفترة وجيزة‬
‫حتى تصل إلى درجة الحرارة المناسبة فيضم الجزءان واحدا على األخر و‬
‫يضغط عليهما بالطرق على السندان‪.‬‬
‫و فيه يستخدم التيار الكهربى لتوليد الطاقة الحرارية الالزمة لعملية اللحام‬
‫فيجرى التسخين الموضعى لألجزاء المطلوب توصيلها عن طريق مقاومة‬
‫كهربية يمر بها تيار كهربى بين قطبين يحدثان ضغطا مناسبا على تلك‬
‫األجزاء‪ ،‬و يتسبب مرور التيار فى توليد طاقة حرارية تصهر ما بين نقط‬
‫تالمس القطبين‪ ،‬فتتالحم القطعتان عند هذه المواضع‪ ،‬و هذا و يشترط ان‬
‫يكون اللحام خاليا من األكاسيد و الشوائب حتى تخرج وصلة لحام قوية‪.‬‬
‫يمكن لعملية لحام المقاومة الكهربية أن تتخذ عدة صور متباينة حسب شكل األقطاب و‬
‫مواضع اللحام و تشمل‪-:‬‬
‫‪ ‬لحام النقطة (البنطة) ‪Spot Welding‬‬
‫‪ ‬لحام الخط ‪Seam Welding‬‬
‫‪ ‬لحام البروز ‪Projection Welding‬‬
‫‪ ‬لحام التناكب ‪Butt Welding‬‬
‫‪ ‬لحام التناكب الوميضى ‪Flash Butt Welding‬‬
‫‪ ‬لحام الصدم ‪Percussion Welding‬‬
‫يقوم على فكرة توليد الحرارة بين سطحين متالمسين يتحركان بالنسبة‬
‫لبعضهما تحت تأثير ضغط خارجى و عندما تصل درجة الحرارة الى درجة‬
‫اإلنصهار توقف الحركة النسبية مع اإلحتفاظ بتسليط الضغط الخارجى حتى‬
‫يتم اللحام‪.‬‬
‫كل الطرق السابق ذكرها تستخدم فقط للحام معدنين من نفس‬
‫النوع‪ .‬أما اذا أردنا لحام معدنين مختلفين فيستخدم نوع اخر من‬
‫أنواع اللحامات يسمى لحام المؤنة (لحام القصدير)‬
‫تجرى عملية التوصيل فى هذه األنواع باإلستعانة بسبائك غير حديدية كسبائك‬
‫النحاس و الفضة فى لحام المؤنة و سبائك القصدير و الرصاص فى اللحام‬
‫اللين مع استخدام مساعد تالحم يتم اختياره ليتناسب مع المعادن المراد‬
‫توصيلها‬
‫تستخدم هذه الطريقة لتوصيل األجزاء المعدنية و الغير معدنية (الخشب و‬
‫الغراء) و تنقسم المواد الالصقة الى‪:‬‬
‫‪‬مواد ذات لدونة حرارية‬
‫‪‬مواد متصلدة عند التسخين‬
‫وال يصلح النوع األول عند درجات الحرارة المرتفعة لفقدها لمتانتها و‬
‫مقاومتها للحرارة و النوع الثانى يمكن تنشيطها بالحرارة‪.‬‬
Butt Joint
Butt joint- a joint
between two
members aligned
approximately in
the same plane
Corner Joint
Corner joint - a joint
between two
members located at
right angles to each
other
T-Joint
T- joint - a joint
between two
members located
approximately at right
angles to each other
in the form of a T
Lap Joint
Lap Joint- a joint
between two
overlapping
members
Edge Joint
Edge joint- a joint
between the edges
of two or more
parallel or nearly
parallel members
‫تشغيل المعادن‬
‫تشغيل ميكانيكي‬
‫تشغيل يدوي‬
‫القطع باالجنه القطع بالمنشار القطع بالمبارد‬
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‫خراطة‬
‫ثقب‬
‫تفريز‬
‫تجليخ‬
Dr.Reem AlKadeem
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3
10-30 ‫زاوية الجرف‬
Rake Angle
γ
‫األداة‬Tool
β
6-12 ‫زاوية الخلوص‬
α
Clearance Angle
‫الشغلة‬Work Piece
Dr.Reem AlKadeem
25
4
‫التشغيل اليدوى – المنشار‬
‫‪25‬‬
‫‪5‬‬
‫‪Dr.Reem AlKadeem‬‬
‫•يعتبر المبرد من األدوات متعددة الحدود القاطعة‪.‬‬
‫•تستخدم المبارد فى تنعيم وتشطيب األسطح‪.‬‬
‫•يوجد أشكال عديدة من المبارد تمشيا مع اإلستخدام‪:‬‬
‫المربع – المبطط – المثلث – نصف الدائرة‪.‬‬
‫•زوايا قطع أسنان المبرد‪:‬‬
‫–زاوية جرف سالبة ‪ 5‬درجات‬
‫–زاوية اداة ‪ 40‬درجة‬
‫–زاوية خلوص ‪ 55‬درجة‬
‫‪-5‬‬
‫‪40‬‬
‫‪55‬‬
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‫‪Dr.Reem AlKadeem‬‬
‫عمـليـات التـشغــيــل‬
‫تشطيب‬
‫تشغيل‬
(Finishing)
(Machining)
‫التجليخ‬
Grinding
‫التفريز‬
Milling
‫الكــشــط‬
‫الخراطة‬
Turning Shaping
Dr.Reem AlKadeem
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7
Chuck
Tail Stock
Tool Post
Dr.Reem AlKadeem
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1
Dr.Reem AlKadeem
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2
‫حركة تغذيةخطية‬
‫حركة القطع دورانية‬
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‫خراطة مخروط‬
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‫‪Dr.Reem AlKadeem‬‬
‫خراطة خارجية‬
Dr.Reem AlKadeem
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5
Dr.Reem AlKadeem
26
6
Dr.Reem AlKadeem
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7
‫خراطة خارجية‬
Dr.Reem AlKadeem
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8
Dr.Reem AlKadeem
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9
‫خراطة قالووظ‬
‫ثقب‬
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27
0
Dr.Reem AlKadeem
27
1
‫عملية قطع و خنق‬
Dr.Reem AlKadeem
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2
Dr.Reem AlKadeem
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3
© 2009 Dr. Eng. Mahmoud El-Sharief
© 2009 Dr. Eng. Mahmoud El-Sharief