PRESENTED BY- NAME - SOUMYABRATA BASAK ROLL - 14MS06005

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Engineering Materials and Properties

Definition Of Materials Of Engineering

Materials of Engineering refers to selecting the correct materials for the application in which the

engineered part is being used. This selection process includes choosing the material, paying

attention to its specific type or grade based on the required properties.

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Material Selection

Function

Material Shape

Process

Material selection and process cannot be separated from the shape and the function of the product, two way interaction.

Function dictates the choice of material and shape.

Process interacts with shape.

Process is influenced by material

Shape restricts the choice of material and process.

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Engineering Materials Classification

Engineering Materials

Metals & Alloy Non Metals

Steel

Stainless steel

Cast iron

Ferrous Non-ferrous

Aluminum

Copper

Zinc

Titanium

Tungsten

Thermoplastics

Acrylic

Nylon

ABS

Polyethylene

Polycarbonate

PVC

Thermosets

Phenolic

Polymide

Polyester

Elastomers

Rubber

Polyurethane

Silicone

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Engineering Materials

Materials

Metals Non MetalsCeramics

Glass

Carbides

Nitrides

Oxides

Graphite

Diamond

Glasses

Glass ceramics

Composites

Reinforced plastics

Metal-Matrix

Ceramic-Matrix

Laminates

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Properties of Materials

Properties of Materials

Metallurgical/Mechanical Properties

Hardness

Hardness

Toughness

Fatigue (cyclic load)

Creep (temp / time)

Physical & chemicalProperties

Thermal conductivity

Thermal expansion

Electrical conductivity

Magnetic properties

Corrosion

Density

Melting point04/08/23

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• Tensile stress, : • Shear stress, :

Area, A

Ft

Ft

FtAo

original area before loading

Area, A

Ft

Ft

Fs

F

F

Fs

FsAo

Stress has units: N/m2 or lb/in2

Engineering Stress

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Engineering Strain

Strain is dimensionless.

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Material StrengthStandard Tensile Test

Standard Specimen

Ductile Steel (low carbon)

Sy – yield strength

Su – fracture strength

σ (stress) = Load / Area

ε (strain) = (change in length) / (original length)

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F

bonds stretch

return to initial

1. Initial 2. Small load 3. Unload

Elastic means reversible.

Elastic Deformation

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1. Initial 2. Small load 3. Unload

Plastic means permanent.

planes still sheared

F

elastic + plastic

bonds stretch & planes shear

plastic

Plastic Deformation (Metals)

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(c)2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning™ is a trademark used herein under license.

1. Localized deformation of a ductile material during a tensile test produces a necked region. 2.The image shows necked region in a fractured sample

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Material StrengthDifferent grade of steel Plastics

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Natural Rubber

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• - the extent of plastic deformation that a material undergoes before fracture, measured as a percent elongation of a material.

% elongation = (final length, at fracture – original length) / original length

Ductility

Common Mechanical Properties• – the

highest stress a material can withstand and still return exactly to its original size when unloaded.

Yield Strength (Sy)

• - the greatest stress a material can withstand, fracture stress.

Ultimate Strength (Su)

• - the slope of the straight portion of the stress-strain curve.

Modulus of elasticity (E)

• - the capacity of a material to absorb energy within the elastic zone (area under the stress-strain curve in the elastic zone)Resilience

• - the total capacity of a material to absorb energy without fracture (total area under the stress-strain curve in the elastic zone)Toughness

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MetalsThe most common materials characteristics which are useful in design, production purpose in various Industries are :-

• Conduct electricity and heat.

• Have relatively high melting point, some metal alloys can withstand temp. up to 2200 oC.

• Metals are ductile, they can be shaped by extrusion (hot or cold), rolling, forging and drawing.

• Metals are easy to machine with precision.

• Metals are strong, stiff, and tough.

• They can be made stronger by alloying and heat treatment.

• Metals are vulnerable to corrosion.

THANK YOU

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References

• www.wikipedia.org (collection of theory)

• www.google.com (photo collection)

• Materials Science And Engineering-Callister’s

• Physical Metallurgy-V.Raghavan

• Mechanical Metallurgy-George E. Dieter

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THANK YOU

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