Introduction to Materials Testing

VII SEMESTER
[R 2017 - Open Elective]
OML751 - TESTING OF MATERIALS
S.Thirumalvalavan
Assistant Professor/ Mechanical
E-mail: thirumalbemech@gmail.com
UNIT-I INTRODUCTION TO MATERIALS TESTING
1

OML751 – TESTING OF MATERIALS - SYLLABUS
UNIT I INTRODUCTION TO MATERIALS TESTING 9
Overview of materials, Classification of material testing, Purpose of
testing, Selection of material, Development of testing, Testing
organizations and its committee, Testing standards, Result Analysis,
Advantages of testing.
2@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.

➢ Overview of materials,
➢ Classification of material testing,
➢ Purpose of testing,
➢ Selection of material,
➢ Development of testing,
➢ Testing organizations and its committee,
➢ Testing standards,
➢ Result Analysis,
➢ Advantages of testing.
UNIT-I INTRODUCTION TO MATERIALS TESTING

“Without materials, there is NO engineering“
What is Material.?
• The matter from which a thing is or can be made.
• A material is a substance or mixture of substances that constitutes an object. Materials can
be pure or impure, living or non-living matter.
• Materials can be classified based on their physical and chemical properties, or on their
geological origin or biological function.
• Material science is the study of materials and their applications.
UNIT - I
Chapter 1. OVERVIEW OF MATERIALS

What are Materials?
• That’s easy! Look around.
• Our clothes are made of materials, our homes are made up of
materials. [ Bricks, Wood, Gate: Iron, Steel – SS, MS, Glass
windows, vinyl sliding, metal silverware, ceramic dishes…]
• Most things are made from many different kinds of materials.
Common type of materials
Metals Ceramics Polymers
Hybrids (Composites)
& Glasses

Which deals with the discovery and design of new materials.
• It all about the raw materials and how they are processed
• That is why we call it materials ENGINEERING
• Minor differences in Raw materials or processing parameters can mean
major changes in the performance of the final material or product.
What is material science.?

Materials Science and Engineering
Materials Science
• The discipline of investigating the relationships that exist between the structures
and properties of materials.
Materials Engineering
• The discipline of designing or engineering the structure of a material to produce a
predetermined set of properties based on established structure-property
correlation.
Four Major Components of Material Science and Engineering:
• Structure of Materials
• Properties of Materials
• Processing of Materials
• Performance of Materials

History of Materials
• Man has been studying materials since before leaving the cave.
• Due to lack of communication, early man spent hundreds of millennia
experimenting with stone tools.
• The first metal tools appeared perhaps only six thousand years ago.
• As our knowledge of materials grows, so does the sophistication of our
tools.
• The more sophisticated our tools, the more sophisticated our
accomplishments.

And Remember: Materials “Drive” our Society!
Ages of “Man” we survive based on the materials we control
• Stone Age – naturally occurring materials
• Special rocks, skins, wood
• Bronze Age
• Casting and forging
• Iron Age
• High Temperature furnaces
• Steel Age
• High Strength Alloys
• Non-Ferrous and Polymer Age
• Aluminum, Titanium and Nickel (superalloys) – aerospace
• Silicon – Information
• Plastics and Composites – food preservation, housing, aerospace and higher speeds
• Exotic Materials Age?
• Nano-Material and bio-Materials – they are coming and then …

Steel Age (90% structural purposes)
In 1980 2019
60mt 996.3mt China
10mt 111.2mt INDIA
100mt 99.3mt Japan
110mt 87.9mt USA
* INDIA is the 2th largest steel producing country

Doing Materials!
• Engineered Materials are a function of:
• Raw Materials Elemental Control
• Processing History
• Our Role in Engineering Materials then is to understand the application
and specify the appropriate material to do the job as a function of:
• Strength: yield and ultimate
• Ductility, flexibility
• Weight/density
• Working Environment
• Cost: Lifecycle expenses, Environmental impact*
* Economic and Environmental Factors often are the
most important when making the final decision! 12@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.

Example of Materials Engineering Work – Hip Implant
• With age or certain illnesses joints deteriorate.
Particularly those with large loads (such as hip).

Example – Hip Implant

Solution – Hip Implant
• Key Problems to overcome:
• fixation agent to hold
acetabular cup
• cup lubrication material
• femoral stem – fixing agent (“glue”)
• must avoid any debris in cup
• Must hold up in body chemistry
• Must be strong yet flexible
Acetabular
Cup and
Liner
Ball
Femoral
Stem
Standard Implant Component Materials: Metal on Metal (MOM), Polyethylene and Metal on
Polyethylene (MOP), Ceramic on Metal (COM), Ceramic on Polyethylene (COP), Ceramic on
Ceramic (COC).
Nowadays hip joint prostheses are made with metals, ceramics and plastic materials.
Most used are titanium alloys, stainless steel, special high-strength alloys, alumina, zirconia,
zirconia toughened alumina (ZTA) 15@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.

The Golden Gate Bridge north of San Francisco, California, is one of the most famous and most
beautiful examples of a steel bridge.
“Metals” give impressions of
“structural steels”.
Metallic Materials have :
1) High strength and formability
2) Ductility (plastic deformation)
Most of the bridges and high
rising buildings are
constructed with steels.
Golden Gate Bridge, connecting San Francisco and Martin County, opened on May 27, 1937,
as the longest suspension bridge of 2,737 meters. 16@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.

Pamban Bridge, Rameswaram, Tamil Nadu, India

Thiruvalam Rajendra Iron Bridge, Vellore, Tamil Nadu, India
Approx. 500 m long iron bridge

The length between towers :800m
World 5th longest cabled bridge (사장교)
South korea - Incheon Bridge (6 lanes) : Songdo – Incheon Int’l Airport
Total length : 21.38㎞, Length over the sea : 12.12㎞

Classification of Materials
Monolithic
Materials
Hybrids
Ceramics and ceramic alloys
& Glasses
Metals
(& Metallic Alloys)
Polymers (& Elastomers)
Sandwich
Composite
Lattice
Segment
Composites: have two (or more)
solid components; usually one is a
matrix and other is a reinforcement
Sandwich structures: have a
material on the surface (one
or more sides) of a core
material
Lattice* Structures: typically a
combination of material and space
(e.g. metallic or ceramic forms,
aerogels etc.).
Segmented Structures: are divided in 1D, 2D
or 3D (may consist of one or more materials).
Hybrids are
designed to improve
certain properties of
monolithic materials
Classification of composites.
▪ Based on the matrix: metal matrix, ceramic matrix, polymer matrix.
▪ Based on the morphology of the reinforcement: particle reinforced (0D), fiber reinforced (1D),
laminated (2D). 20
Hybrids are
designed to improve
certain properties of
monolithic materials
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC.

Another way of classification

23
Periodic Table of the Elements

List the Major Types of MATERIALS That You Know?
METALS
CERAMICS
POLYMERS
COMPOSITES
• Metals
• Steel, Cast Iron, Aluminum,
Copper, Titanium, many others
• Ceramics
• Glass, Concrete, Brick, Alumina,
Zirconia, SiN, SiC
• Polymers
• Plastics, Wood, Cotton (rayon,
nylon), “glue”
• Composites
• Glass Fiber-reinforced polymers,
Carbon Fiber-reinforced polymers,
Metal Matrix Composites, etc.

The Materials Selection Process
1. Pick Application Determine required Properties
2. Properties Identify candidate Material(s)
3. Material Identify required Processing
Processing: changes structure and overall shape
ex: casting, sintering, vapor deposition, doping
forming, joining, annealing.
Properties: mechanical, electrical, thermal,
magnetic, optical, deteriorative.
Material: structure, composition.

BUT : Properties depend on Structure (strength or hardness)
Hardness(BHN)
Cooling Rate (ºC/s)
100
200
300
400
500
600
0.01 0.1 1 10 100 1000
(d)
30 mm
(c)
4 mm
(b)
30 mm
(a)
30 mm
AND :Processing can change structure! (see above structure Vs Cooling Rate)

Another Example: Rolling of Steel
◼ At h1, L1
◼ low UTS
◼ low YS
◼ high ductility
◼ round grains
◼ At h2, L2
◼ high UTS
◼ high YS
◼ low ductility
◼ elongated grains
Structure determines Properties BUT Processing determines Structure!

Common materials: with various ‘viewpoints’
Glass: amorphousCeramics
Crystal
Graphite
PolymersMetals
What are functionally graded materials?
▪ In functionally graded materials (FGM) the property varies from one side of the material (structure) to the
other.
▪ E.g the outer surface may be made hard and abrasion resistant, while the interior could be made tough.
▪ The gradation in function could be obtained by composition changes, microstructure differences (via heat
treatment), etc.
Gradation of function

MATERIALS SCIENCE & ENGINEERING
PHYSICAL MECHANICAL ELECTRO-
CHEMICAL
TECHNOLOGICAL
• Extractive
• Casting
• Metal Forming
• Welding
• Powder Metallurgy
• Machining
• Structure
• Physical
Properties
Science of Metallurgy
• Deformation
Behaviour
• Corrosion
❑ The broad scientific and technological segments of Materials Science are shown
in the diagram below.
❑ To gain a comprehensive understanding of materials science, all these aspects
have to be studied.
• Thermodynamics • Kinetics

The Materials Tetrahedron
❑ A materials scientist has to consider four ‘intertwined’ concepts, which are schematically shown as the
‘Materials Tetrahedron’.
❑  When a certain performance is expected from a component (and hence the material constituting the
same), the ‘expectation’ is put forth as a set of properties.
 The material is synthesized and further made into a component by a set of processing methods
(casting, forming, welding, powder metallurgy etc.).
 The structure (at various lengthscales) is determined by this processing.
 The structure in turn determines the properties, which will dictate the performance of the
component.
❑ Hence each of these aspects is dependent on the others.
The broad goal of Materials Science &
Engineering is to understand and
‘engineer’ this tetrahedron

Science
ProcessingProperty
Structure
Performance
Engineering
“Right materials for the Right Job”
© 2003 Brooks/Cole Publishing / Thomson Learning™

❑ What determines the properties of materials?
➢ Cannot just be the composition!
➔ Few 10s of ppm of Oxygen in Cu can degrade its conductivity (that is why we have Oxygen free high conductivity
copper (OFHC)).
➢ Cannot just be the amount of phases present!
➔ A small amount of cementite along grain boundaries can cause the material to have poor impact
toughness.
➢ Cannot just be the distribution of phases!
➔ Dislocations can severely weaken a crystal.
➢ Cannot just be the defect structure in the phases present!
➔ The presence of surface compressive stress toughens glass.
❑ The following factors put together determines the properties of a material:
➢ Composition
➢ Phases present and their distribution
➢ Defect Structure (in the phases and between the phases)
➢ Residual stress (can have multiple origins and one may have to travel across lengthscales).
❑ These factors do NOT act independent of one another (there is an interdependency).

What are the four founding pillars of materials science?Funda Check
PhysicalStructure
Electromagneticstructure
Thermodynamics
Kinetics
http://thriftydecorchick.blogspot.in/2013/04/ikea-table-turned-farmhouse-table.html
❑ The four pillars of Materials Science and Engineering are (a simplified view!!!):
(i) Physical structure→ Atomic structure (+ Microstructure)
(ii) Electromagnetic Structure→ Electronic and Magnetic structure
(iii) Thermodynamics
(iv) Kinetics
❑ If one gains understanding of these four pillars, one can comprehend most aspects of Material behaviour
and engineer materials for applications.
❑ The subject of Materials Engineering can be envisaged as a confluence of Physics, Chemistry, Biology,
Mechanical Engineering, etc.

❑ There are basically three strategies* available for the use of materials for specific
purposes.
➢ Design a material with better properties
(e.g. materials with better creep resistance at high temperatures).
➢ Protect the material with surface coatings, cooling etc.
(e.g. paint the material to avoid corrosion).
➢ Use ‘sacrificial materials’ to protect the key component
(e.g. use of sacrificial anodes to prevent corrosion).
❑ The obvious has not been stated above− i.e. use more “quantity” of material.
❑ Also, we could do a better design of the component/mechanism/machine/… itself (so that
the “load” on the material is not as much) .
Material usage strategies
* Note: in a given situation, only one/some of these strategies may work.

Examples of smart materials, structures and ‘components’ (/organs) are abound in the biological world. Many of
the ‘stuff’ found in the biological world have amazing design strategies, some of which we are just able to
copy (biomimetic materials) and further use the ‘inspiration’to design newer materials (biognostic materials).
Some of the important qualities, which a smart material can have are listed below.
➢Self reporting: lets us know of changes occurring in the material− e.g. damage accumulation can lead to
magnetization.
➢Responsive: responds to the environment and alters its properties (e.g. photochromatic lenses which darken on
exposure to sun light).
➢Responsive and self healing: responds to the environment or changes within the material and can heal any
deleterious changes (e.g. if cracks grow material is released to heal the cracks).
➢Self cleaning: this is like the ‘gecko effect’, where the surface cleans itself.
➢Self lubricating: an old concept, wherein the material puts up a surface layer which acts like a lubricant (e.g.
Al-graphite composites, wherein the graphite acts like a lubricant).
➢Multi-functional: the material performs multiple roles in a single structure or component. E.g.: (i) the cover of
a mobile can be its power cell too, (ii) an antenna made of shape memory alloy can be transported in collapsed
form and extends itself on heating on-site (envisaged for space applications), (iii) ferroelectric and
ferromagnetic.
Modern material (/component) design: smart materials*

Various materials used in our
Day-to-Day lives

Shirts/trousers
Fabric / polyester/ cotton / Linen /Silk / Canvas /
Velvet / Satin / Wool / Denim

Coins
Cupronickel/ Copper/ Stainless steel
Cupronickel or copper-nickel (CuNi) is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese.

Shoes
Leather/canvas/rubber/plastics
Canvas: Is an extremely heavy-duty plain woven fabric

Lord Murugan temple statue Malaysia
42.7 m (140 ft) Height
1550 Cubic m of concrete
250 ton of steel bars &
300 Lit of gold paints

14-15 April 1912
North Atlantic Ocean
(1490-1635 deaths)
Ductile → Brittle
(Low Impact strength)
Striking in Iceberg
TITANIC

World War II
Due to Winter season,
Weapon materials (Cartridge brass) properties changed to → Brittle
So, Millions of people died

Temple Bell
Bronze

Balloon
Rubber, Polychloroprene, Nylonfabric….

Unit - I
Chapter 2. CLASSIFICATION OF MATERIAL
TESTING
Chapter 3. PURPOSE OF TESTING

In general, What is Testing.?
• In general, testing is to finding out how well something works. In terms of human beings,
testing tells what level of knowledge or skill has been acquired.
• In computer hardware and software development, testing is used at key checkpoints in the
overall process to determine whether objectives are being met.
Example: Assessment test, Blood test, Eye test……..

What is Material Testing.?
• Materials testing : Measurement of the characteristics and behaviour of such substances as
metals, ceramics, or plastics under various conditions.
• The data thus obtained can be used in specifying the suitability of materials for various
applications—e.g., building or aircraft construction, machinery, or packaging.
Why is it Important?
• Materials testing is a respected and established technique which is used to ascertain both
the physical and mechanical properties of raw materials and components.
• It can be used to examine almost anything from human hair to steel, ceramics or composite
materials.

Why Materials Testing is performed?
• Materials Testing is performed for a variety of reasons and can provide a
wealth of information about the tested materials, prototypes or product
samples.
• The data collected during testing and the final test results can be very useful
to engineers, designers, production managers and others.
Here are some of the reasons material testing is important:
• Meeting requirements of regulatory agencies
• Selecting appropriate materials and treatments for an application
• Evaluating product design or improvement specifications
• Verifying a production process

Why are metals tested?
• Ensure quality
• Test Properties
• Prevent failure in use
• Make informed choices in using materials
• Factor of safety : Is the ration comparing the actual stress on a material and
the safe useable stress.

Materials testing breaks down into FIVE major categories
❖ Mechanical testing;
❖ Testing for thermal properties;
❖ Testing for electrical properties;
❖ Testing for resistance to corrosion, radiation, and biological deterioration; &
❖ Nondestructive testing.
Standard test methods have been established by such national and international
bodies as the International Organization for Standardization (ISO), with headquarters in
Geneva, and the American Society for Testing and Materials (ASTM), Philadelphia.

Classification of Test Methods

I. Classification of Destructive Testing:
1. Static testing
Tensile, Compression
Shear, Hardness
Creep, Bending
2. Impact (Dynamic) testing
Charpy & Izod test
Drop ball, Drop dart
Instrumented puncture testing
3. Cyclic testing
Fatigue test
II. Major sources of NDT test
- Liquids, Radiation, Sound
Classification of Non-destructive Testing:
• Visual inspection
• Surface NDT methods
• Thermography, Eddy current testing
• Ultrasonic testing, Radiography
• Acoustic emission testing
Classification of Material Testing
III. Material characterization testing
Microscopy
Spectroscopy
Macroscopic testing

Mechanical Tests
• Mechanical properties are obtained by mechanical testing.
• Mechanical testing is used for developing design data, maintaining quality control,
assisting in alloy development programs and providing data in failure analysis.
• Mechanical testing is usually destructive and requires test specimens of the material to be
machined or cut to the specific shape required by the test method.
• Measurement of the characteristics and behavior of such substances as metals, ceramics,
or plastics under various conditions. The data thus obtained can be used in specifying the
suitability of materials for various applications.
Ex.: building or aircraft construction, machinery, or packing.

Classification of Mechanical Tests
• Destructive tests : In this type of testing, the component or specimen
to be tested is destroyed and cannot be reused.
Ex: Tensile test, Impact test, Bend test, Fatigue test, Torsion test, Creep
test, etc.,
• Non-destructive tests (NDT) : In this type of testing, the component
or specimen to be tested is not destroyed and can be reused after the
test.
Ex: Radiography, Ultrasonic inspection, etc.,

Types of Testing
Mechanical (Destructive) Testing:
• Tensile
• Creep
• Compression
• Bend or flexure
• Hardness
• Impact
• Fatigue
Non destructive Testing:
• Surface NDT methods
• Thermography
• Eddy current testing
• Ultrasonic testing
• Acoustic emission testing
• Radiography
58
You are
going to
study in
NDT
subject

Unit - I
Chapter 4. Selection of Material

Introduction to Roles & Responsibilities of Materials Engineer
Some of Materials Engineer responsibilities are :
1) Design Process:
a) Drawing the basic design.
b) Proper selection of materials :
Selection according to different parameters such as :
Mechanical loads,
Wear,
Electrical insulation,
Thermal properties
Availability & cost.
This includes: Selection of the proper manufacturing processes,
2) Proper choice (selecting) of substitute (alternative) materials when needed.
3) Contributing and evaluating materials tests results,
4) Studying and composing materials data sheets before placing an order,
5) Enhancing the performance of the materials by carrying out research activities.

Introduction to Materials Selection
• One of the most challenging task of materials engineer is the proper selection of the material for a particular
job, e.g., a particular component of a machine or structure.
• An engineer must be in a position to choose the optimum combination of properties in a material at the
lowest possible cost without compromising the quality.
Factors affecting the selection of materials:
(i) Component shape:
The shape and size of a component has great effect on the choice of the processing unit which
ultimately effects the choice of the material. To make it more clear, we consider an example, let the best
possible production method is selected, under given conditions, it is die casting, obviously, now the choice of
the material becomes limited, i.e. one can only choose materials with lower melting points, e.g. aluminium,
zinc, magnesium and thermoplastics.
(ii) Dimensional tolerance:
There are some materials which can be finished to close tolerance while others cannot. Obviously, the
required dimensional tolerance for finished components will, influence the choice of materials.
(iii) Mechanical properties:
To select a suitable material for specific conditions, all mechanical properties, e.g., toughness,
hardness, strength, etc. guide us.

Introduction to Materials Selection
(iv) Fabrication (Manufacturing) requirements:
• Method of processing of the material also affects the properties of a component, e.g., forged components can
be stronger than the casted components. Different types of working processes may also give different types of
fibre structure. However, investment casting can provide precise dimensions at low cost in comparison to
machine operations.
Note: fabrication requirements are: castability, i.e., ease in casting a material, weldability-ease in welding the
material, machinability-ease to machine a material, formability-ease to form a material, hardenability etc.
(v) Service requirements:
Service requirements are :
• dimensional stability,
• strength,
• toughness,
• heat resistance,
• corrosion resistance,
• fatigue and creep resistance,
• electrical and thermal conductivity etc.

(vi) Cost :
(a) Cost of the material:
• In most of the cases, the cost of raw material accounts about 50 % of the finished cost. Obviously, the cost of
the material is a major factor which influences the choice of the material or process. We must note that the
use of cheaper material will not always reduce the final cost of the component or product. Use of cheaper
material may be associated with higher processing cost due to large number of operations to be performed
and also more scrap. We can easily see that this sometimes makes the overall cost more than that of
expensive raw material in combination with low processing cost due to lesser number of operations and
lesser scrap.
(b) Cost of processing:
• In most of the industries, the processing cost (labour cost) and other costs such as overhead costs account for
about 50% of the production cost. Overhead cost in automatic industries is much more than the other costs.
If one can somehow reduce all such costs, the total production cost will automatically reduce.
(vii) Availability of the material:
• We may find that sometimes the availability of the material becomes a governing factor. When the desired
material supply is limited, then a costly material which is available in ample quantity may be chosen.
(viii) Environment
• The effect that the service environment has on the part; The effect the part has on the environment; The
effect that processing has on the environment

Procedure for materials selection
• The selection of an appropriate material and its subsequent conversion into a useful
product with desired shape and properties can be a rather complex process. Nearly every
engineered item goes through a sequence of activities that includes:
Design → material selection → process selection → production → evaluation → and possible
redesign or modification

Factors affecting selection of materials
65
➢ The selection of a specific material for a particular use is a very complex process.
However, one can simplify the choice if the details about:
(i) operating parameters,
(ii) manufacturing processes,
(iii) functional requirements
(iv) cost considerations are known.

Selection of Materials according to their Mechanical Properties:
Mechanical properties describe the behavior of material in terms of deformation and resistance
to deformation under specific mechanical loading condition. These properties are significant as
they describe the load bearing capacity of structure. Elastic modulus, strength, hardness,
toughness, ductility, malleability are some of the common mechanical properties of engineering
materials:
1. Selection for Static Strength : Static strength can be defined as: the ability to resist a short-
term steady load at moderate temperatures without breaking or crushing or suffering
excessive deformations.
2. Selection for stiffness : the ability of a material to resist deflection when loaded.
3. Selection for fatigue resistance : The failure of a component when subject to fluctuating
loads is as a result of cracks which tend to start at some discontinuity in the material and
grow until failure occurs.
4. Selection for toughness : can be defined as the resistance offered by a material to fracture. A
tough material is resistant to crack propagation.

5. Selection for creep and temperature resistance : The creep resistance of a metal can be
improved by incorporating a fine dispersion of particles to impede the movement of dislocations.
6. Selection for corrosion resistance :
7. Selection for wear resistance : is the progressive loss of material from surfaces as a result of
contact with other surfaces. It can occur as a result of sliding or rolling contact between surfaces
or from the movement of fluids containing particles over surfaces.
Mechanism of wear
1. Adhesive wear
2. Abrasive wear
3. Corrosive wear
4. Surface fatigue
8. Selection for thermal properties
9. Selection for electrical properties
10. Selection for magnetic properties

Selection of Material
There are many thousands of different engineering materials available today. But they
can be placed into one or other of the following categories:
1. Metals, 2. Polymers, 3. Ceramics and inorganic glasses, 4. Composites.
• All materials exhibit many different properties and qualities. The properties of
material provide a basic for predicting its behavior under various conditions.
• An engineer must have wide knowledge of materials and their properties so that he
may select a suitable material for his product.
Metals – Strong, Heat Transfer, Deformable
Ceramics – Hard but Brittle, Insulation
Polymers – Light, Flexible, Compressible
Composites – Strength of Fiber & Flexibility of Polymer

Material Properties and Qualities
1. Physical properties – Colour, density, melting point, size, shape, finish…
2. Chemical properties – Corrosion resistance, atomic weight, atomic number, chemical
composition…
3. Mechanical properties – Strength, elasticity, plasticity, ductility, brittleness,
hardness…
4. Electrical properties – Resistivity, Conductivity, capacitivity, dielectric constant…
5. Magnetic properties – Relative permeability, reluctivity, hysteresis…
6. Thermal properties – Specific heat, thermal capacity, conductivity, thermal fatigue…
7. Technological properties – Malleability, machinability, weldability, castability,
formability…
8. Aesthetic properties – Appearance, texture and ability to accept special finishes.
9. Economic properties – Raw material and processing cost, availability.
10. Other properties – Optical, acoustical, and physiochemical properties

Factors to be considered for the selection of materials
Following factors should be considered:
1. Availability
2. Cost
3. Mechanical Properties :
4. Manufacturing consideration :
1. Availability : The Material should be readily available in market in large enough quantities
to meet the requirement.
2. Cost : For every application, there is limiting cost beyond which the designer cannot go.
When the limit exceeded the designer has to consider an alternative material.
In cost analysis, there are two factors namely cost of material and the cost of
processing the material into finished goods.
It is likely that the cost of material might be low but the processing may involve costly
machining operations.

3. Mechanical properties
• Mechanical properties are those characteristics of material that describe its behavior under
the action of external forces..
• Sound knowledge of mechanical properties is very essential for an engineer to select a
suitable material for his various design purposes.
Types of Mechanical Properties: There are many mech. Properties of a metal, some of the
important mech. Properties are listed below,
Ductility Malleability
Toughness Brittleness
Brittleness Stiffness
Hardness Resilience
Plasticity Creep
Elasticity Endurance
Strength Impact strength Fatigue

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3
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Factors affecting mechanical properties
• Though there are number of factors affect mechanical properties, the following factors
highly influencing the mechanical properties,
1. Grain size
2. Heat treatment
3. Atmospheric exposure
4. Low and high temperature
Technological properties are those which have a bearing on the processing and/or
application of materials.
• These properties are highly describe qualities in the shaping, forming and fabrication of
materials for useful properties.
Some of the important Technological Properties are listed below,
Machinability, Castability, Weldability, Formability or workability

4. Manufacturing consideration :
• It is important consideration in selection of materials.
• Sometimes, expensive materials are more economical than low cost material,
which difficult to machine.

Man & Materials
From : Stone age
To : Space age

Importance of Material Selection
Columbia Space Shuttle Failure
•Safety Aspects
The Space Shuttle Columbia
disaster was a fatal incident in the
United States space program that
occurred on February 1, 2003,
when the Space Shuttle Columbia
disintegrated as it reentered the
atmosphere, killing all seven crew
members.
Brown, Husband, Clark, Chawla,
Anderson, McCool, Ramon

Erosion of Pump Impeller
Plant Life Aspects

Iron Pick Up by DM (Demineralized) Water
Product Contamination

Bacterial Contamination in Food Industry
Process Contamination

Reactor Explosion due to Temperature Rise
Equipment Failure

Unit - I
Chapter 5. Development of testing

Development of Testing
@ S. Thirumalvalavan, AP/Mech, 5104 - AEC. 96
Formulation in test development

Stages in development of testing

Unit - I
Chapter 6. Testing organizations and its committee

TESTING ORGANIZATIONS AND ITS COMMITTEE
• Standard and specification helps to develop common language for developers, designers,
fabricators, purchasers and suppliers, end users.
• Standard: - A technical document based on consolidated results of science, technology and
experience approved by a standardizing body for the benefits of the people.
• Standardization: - It is the activity giving solutions for repetitive applications to problems,
essentially in the sphere of science, technology and economics aimed at the achievement of
the optimum degree of order in a given contest.
• Technical specification: - A document which lays down characteristics of a product or a
service such as levels of quality performance, safety or dimensions

TESTING STANDARDS
• Basic standard: - It contains general provisions for one particular field.
• Terminology standard: - It is concerned with terms, definitions, explanatory notes,
illustrations, examples, etc.
• Testing standards: - A standard concerned exclusively with test methods, supplemented
with other provisions related to testing such as sampling, statistical methods and
sequence of testing.
• Product standard: - A standard specifying some or all the requirements to be met by a
product.
• Safety standard: - A standard aimed at the safety of the people and goods.

INTERNATIONAL ORGANIZATION
• British Standard Institution (BSI):- BSI was formed in 1901, producing standards in all fields.
• American National Standard Institute (ANSI): ANSI is the premier standardization body in USA.
• American Society for Testing & Materials (ASTM): ASTM is a Scientific & Technical Organization
formed for the development of standards on characteristics and performance of materials,
products, systems and services and promotion of related knowledge.
• Deutsche Institute Fur Normung (DIN):- The German standard organization was formed in 1917
producing standards in all the fields in German language which published in English, French and
Spanish also.
• Bureau of Indian Standards (BIS): - BIS is engaged in developing national standards and their
revision/review from time to time.

International Organizations For Material Testing
The following are some global organizations which are involved in setting up of "testing standards" and active
research for material analysis and reliability testing.
• American Association of Textile Chemists and Colorists (AATCC)
• American National Standards Institute (ANSI)
• American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)
• ASTM International
• Cooper Research Technology
• American Society of Mechanical Engineers (ASME)
• Society of Automotive Engineers (SAE)
• International Organization for Standardization (ISO)
Global Research Laboratories for Material Testing
• Materials Analysis and Technology
• Metallurgical Services in Mumbai, India
• Razi Metallurgical Research Center, RMRC

Organization chart

Unit - I
Chapter 7. Testing Standards

Material Testing Standards
• Material Testing Standards provide a unified reference for test methods, equipment, and
industry-specific usage scenarios and specifications for a wide array of materials and test
environments.
• Ranging from medical devices that are implanted within a patient's body, to key mechanical
components relied upon by planes and automobiles, these standards provide vital
information and instructions on how to attain it for many different industries.
1. Metallic Material Testing Standards
2. Medical Material Testing Standards
3. Flammable Material Testing Standards
4. Radiation Hardness Material Testing Standards
5. Material Test Methods

1. Metallic Material Testing Standards
• Metallic Material Testing Standards focus on hardness, tensile, and fatigue testing,
approaching the issues from multiple angles to provide a range of information.
• In addition, metallic material testing standards cover corrosion testing, weld testing, and
other areas of interest. Together, standardized testing provides valuable information to
determine the reliability of metallic materials and the products and structures using them.
• It includes, Bearings, Corrosion testing, Fatigue, Hardness, Tensile, Impact, Weld test, Other
metallic standards.
Example,
ISO 4384-1:2019 : Plain bearings - Hardness testing of bearing metals - Part 1: Multilayer
bearings materials
ISO 4384-2:2019 : Plain bearings - Hardness testing of bearing metals - Part 2: Solid materials
ASTM E18-20 : Standard Test Methods for Rockwell Hardness of Metallic Materials
ASTM E8/E8M-16ae1 : Standard Test Methods for Tension Testing of Metallic Materials
Etc.,

2. Medical Material Testing Standards
• Medical Materials Testing addresses the testing and materials and products that are
designed to be compatible with the human body, including dental materials, joint
prostheses, and other medical devices that will contact blood or other tissues.
• Given the vital nature of medical devices, testing procedures for both the devices and their
components is critical for their safety and ongoing reliability.
Example:
ASTM F2118-14 : Standard Test Method for Constant Amplitude of Force Controlled Fatigue
Testing of Acrylic Bone Cement Materials
ASTM F732-17 : Standard Test Method for Wear Testing of Polymeric Materials Used in
Total Joint Prostheses

3. Flammable Material Testing Standards
• Fire related Material Testing Standards cover test procedures for a range of industries.
Personal Protective Equipment (PPE), aerospace, building construction materials,
insulation, and others all rely on strict material testing procedures.
• These material testing standards also detail laboratory testing procedures to measure
flammability, burning characteristics, heat transfer, lower flammability limit (LFL), lower
explosive limit (LEL), and other vital characteristics.
Example:
• ASTM D1929-20 : Standard Test Method for Determining Ignition Temperature of Plastics
• ASTM D3675-19 : Standard Test Method for Surface Flammability of Flexible Cellular
Materials Using a Radiant Heat Energy Source

4. Radiation Hardness Material Testing Standards
• Radiation-Hardness Standards provide guides and standard practices for testing the effects
of radiation on electronics, their components, and their systems.
• In addition to electronics, some of these methods can be applied to other materials. These
standards address both the source of the radiation and the detector, as well as the test
environment and applicability of the results.
Example:
ASTM E721-16 : Standard Guide for Determining Neutron Energy Spectra from Neutron
Sensors for Radiation-Hardness Testing of Electronics
ASTM E1249-15 : Standard Practice for Minimizing Dosimetry Errors in Radiation Hardness
Testing of Silicon Electronic Devices Using Co-60 Sources

5. Material Test Methods
• Material Testing Standards are diverse in their focus, serving as integral parts of many
industries and providing the standard test methods for materials of every sort. Polymers,
paints, rubber, ceramics, glass, and other materials are covered here, as well as industry
specific tests such as those for the nuclear, shipping, or the aerospace industries.
• Due to the sheer breadth of the standards offered by ANSI and the variety within, the
standards below are just a sample. To see more standards relevant to your industry, use
the search function above to find those that you need.
Example: ASTM D4762-18 : Standard Guide for Testing Polymer Matrix Composite Materials
ASTM F790-18 : Standard Guide for Testing Materials for Aerospace Plastic Transparent
Enclosures

Physical Testing Standards and Mechanical Testing Standards
https://www.astm.org/Standards/physical-and-mechanical-testing-standards.html
List of ASTM International standards
https://en.wikipedia.org/wiki/List_of_ASTM_International_standards

A simplistic but idealized working definition…
Standard - a document, developed and used by consensus of the
stakeholders, which describes how a product is to be obtained or used.
• document - can be electronic or paper
• stakeholders – includes anyone with an interest without restriction
• product - can include hardware, software, analysis result, test result, protocol,
definition, etc.
• obtained or used - can mean designed, built, procured, calculated,
tested, etc.
What is a Standard?

✓Best practices (things that have worked well)
✓Lessons learned (things that haven’t worked well)
✓Recent research results
• Able to stimulate further research in related areas
Standards cannot be created for every situation
Sometimes necessary in real practice for a subject matter expert
to extrapolate from one or more existing standards and design
principles to solve a specific need
What Does (and Doesn’t) Go Into a Standard?

“The engine of national and global commerce is driven by standards.”
Good standards – those with credibility, integrity, and marketplace acceptance – reduce
procurement costs, improve products, expand markets, and/or lower risk
Standards do this by…
▪ Reducing duplication of effort or overlap and combining resources
▪ Bridging of technology gaps and transferring technology
▪ Reducing conflict in regulations
▪ Facilitating commerce
▪ Stabilizing existing markets and allowing development of new markets
▪ Protecting from litigation
▪ …and more…
Benefit of Standards

Practicing Engineers Need Standards
Why?
To Produce Their Products Efficiently
• Deliverable products must be designed and built - they make use of procured items and
must themselves be procured
• Each of these phases, procurement especially, requires specification
• Effective specification requires standards

• Purpose of standards
• Types of standards
• Sources of standards
• Standards Development Processes
▪ Who controls the standards
▪ How to update/correct existing standards
▪ How to create new standards
• Most Important standards for their discipline
• Proper use of those standards
What You Need To Know

ASTM currently recognizes five specific types:
1. Specification (in the sense of a procurement document)
2. Test Method (produces a test result)
3. Terminology (or definitions)
4. Practice (a protocol that doesn’t produce a test result)
5. Guide (informational description of a number of options)
Types of Standards
117
Ref: ASTM E8M1.pdf

“The good thing about standards is that there are many of them”
• A product should be designed to comply with industry standards (such as the requirements of
dimensional, physical, mechanical, electrical properties).
• While designing to standards does not ensure a safe product, standards do tend to create safer
products.
• Advertise and market wisely. Occasionally, a company creates potential product misuse
situations though its advertisements, marketing materials, and sales personnel. Product liability
loss prevention is not the sole responsibility of the product designer or manufacturer;
misrepresentation and exaggeration in advertisements and marketing materials may also be
involved.
• The infomercial has underscored the importance of testing.
Standards and Testing

• According to a product’s nature, specifications and international regulations, various types of tests such as
▪ Safety tests
▪ Life tests (reliability)
▪ Functional tests, and
▪ Packaging tests
must be preformed to assure conformance and quality.
• There are many different types of products and their associated tests.
• Chemical Testing
• Construction Materials
• Electrical and Electronic Products
• Food
• Textiles and Garments
• Toys and Children's Products, etc.
Product Testing

• Manufacturers in gaining access to key international markets such as North America, Europe, Japan and
Australia, their products must be in compliance with international regulations and standards. You may
have seen some of the following marks/labels.
• Acquiring these certifications can be expensive and time-consuming.
• At the beginning of 1992, the European
Single Market was created. A series of
Directives are intended to provide controls
on product design, with the principal
objective being to provide “common’”
standards for product safety requirements
across the European Community.
Conformance to Standards Opens Markets

Unit - I
Chapter 8. Result Analysis

Result Analysis
• It is very important by sharing the knowledge of result or development with others which
leads to the various development of test result by other scientist or researchers.
• The steps to be followed for description of test report
✓Statement of the problems
✓Materials, methods and procedures used during testing
✓Data presentations & Result analysis → Charts, Graphs, Tabulation, statement, analytic software
Ex: Biovia materials studio, Matlab, Stadd pro, Abacus, autoCAD….
✓Summary, conclusion and discussion
✓Appendices to support findings

Testing Vs Inspection
• Testing is the physical performance of an operation series aimed at
providing quantitate data regarding the properties of a material. It
provides the information about the quality of material.
• Inspection is the observance of a material to determine the presence
or absence of a desired one. It aimed about the controlling the quality
of materials by establishing criteria of acceptance or rejection.

Unit - I
Chapter 9. Advantages of Testing

Advantages of Testing
126
• To determine the suitability of materials for a particular application, for quality
control purposes or to obtain a better understanding of their behavior under
various conditions
• The physical property data obtained by testing is required to design the product
development and failure analysis.
• The testing data are required for to promote the use of plastics.
• Testing feedback helps to aid improved design or quality control procedures.
In other form – Benefits of testing
• Safety issues can be identified
• It provides reliability
• It is cost effective
• It offers reassurance

THANK YOU

Introduction to Materials Testing

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