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Metals

Introduction

Ferrous

Non-ferrous

Advantages & Disadvantages

Metals properties & usage

Metal testing



Metals - Introduction All metals can be classified as either Ferrous or Non-ferrous. Definitions of properties of Materials.

Definitions of properties of Materials.

Ductility The length that a material can be stretched without breaking.

Elasticity The length that a material can be stretched and return to its original length when released.

Heat and Electrical

ConductivityThe measure of how well a material can conduct heat or electricity.

Heaviness The denseness of materials. A dense material will be heavy in relation to its size.

Strength The measure of how a material withstands a heavy load without breaking.

Hardness The resistance a materials has to cutting and surface indentations.

Toughness This describes the amount of energy a material can absorb without breaking. This is theopposite to brittleness. We measure a material's ability to absorb shock.

Tensile StrengthThe maximum force a material can withstand in tension(pulling) compression(squashing) ,

torque(twisting) and shearing(sideways pressure).

Malleability The amount of hammering, pressing and shaping a material can take without breaking.



Metals - Introduction Solid at room temperature, except mercury, which is

liquid.

have very high melting point.

are shiny when they cut.

are good conductors of heat and electricity.

Are usually strong & malleable so they can be hammeredinto shape.



Metals

Ferrous

Introduction

Pig irons

Cast irons

Wrought iron

Steel

Non-ferrous

Introduction

Lead

Copper

Aluminum

Zinc



Ferrous

Introduction

These are metals which contain iron.

They may have small amounts of other metals or other elements

added, to give the required properties.

All ferrous metals are magnetic,

Give little resistance to corrosion



Non-ferrous

Introduction

These are metals which do not contain any iron.

They are not magnetic and

Are usually more resistant to corrosion than ferrous metals.



Advantages of ferrous metals1. High strength to weight ratio

it minimise the substructures cost, whichbeneficial in poor ground condition.

E.g. The Newark Dyke Rail Bridge ² comprises 77meter long, 11.25 meter wide bowstring with 820

tonnes of S355 steel.

1. High quality material readily available worldwide in various

certificate grades.

3. Speed of construction



Advantages of ferrous metals4. Versatility steel suits range of construction methods &

sequences.

5. Modification & repair

6. Recycling

7. Durability

8. Aesthetics steel has a broad architectural possibilities



Disadvantages of ferrous

metals1. Costly waste

2. High cost of final finishing & polishing

3. Need skilled workers

4. Environmental issue



Metals properties & usageFerrous Metals Chooser Chart

Name Composition Properties Uses

Mild

Steel

0.15 to0.30%

carbon

Tough, high tensile strength,

ductile. Because of low

carbon content it can not be

hardened and tempered. It

must be case hardened.

girders, Plates,

nuts and bolts,

general purpose.

High

Speed

Steel

medium carbon,

tungsten,

chromium and

vanadium.

Can be hardened and

tempered. Can be brittle.

Retains hardness at high

temperatures.

Cutting tools for

lathes.

Stainles

s Steel

18% chromium,

and 8% nickeladded.

Corrosion resistant Kitchen draining

boards. Pipes,cutlery, aircraft.

High

Tensile

Steel

Low carbon steel,,

nickel,and

chromium.

Very strong and very tough. Gears, shafts,

engine parts.



Meta s properties & usageFerrous Metals Chooser Chart

Nam

e Com

position Properties Uses

High

Carbon

Steel

0.70% to 1.40%

carbon.

The hardest of the carbon

steels. Less ductile, tough

and malleable.

Chisels, hammers,

drills, files, lathe

tools, taps and

dies.

Mediu

m

Carbon

Steels

0.30% to 0.70%

carbon.

Stronger and harder than

mild steels. Less ductile,

tough and malleable.

Metal ropes, wire,

garden tools,

springs.

Cast

Iron

Remelted pig iron

with small amounts

of scrap steel.

Hard, brittle, strong, cheap,

self-lubricating. Whitecast

iron, grey cast iron,

malleable cast iron.

Heavy crushing

machinery. Car

cylinder blocks,

vices, machine

tool parts, brake

drums, machine

handle and gear

wheels, plumbing

fitments.



Meta s properties & usageNon-Ferrous Metals Chooser Chart

Nam

e Com

position Properties UsesAluminiu

m

Pure Metal Greyish-White, soft,

malleable, conductive to

heat and electricity, It is

corrosion resistant. It can be

welded but this is difficult.

Needs special processes.

Aircraft, boats,

window frames,

saucepans,

packaging and

insulation, pistons

and cranks.Aluminiu

m alloys-

Duralumi

nium)

Aluminium +4%

Copper+1%Mang

anese

Ductile, Malleable, Work

Hardens.

Aircraft and

vehicle parts.

Copper Pure metal Red, tough, ductile, High

electrical conductor,

corrosion resistant, Can

work hard or cold. Needs

frequent annealing.

Electrical wire,

cables and

conductors, water

and central

heating pipes and

cylinders. Printed

circuit boards,

roofs.




Nam

e Com

position Properties UsesBrass 65% copper

+35%zinc.

Very corrosive, yellow in

colour, tarnishes very easily.

Harder than copper. Good

electrical conductor.

Castings,

ornaments,

valves,forgings.

Lead Pure metal The heaviest common

metal. Soft, malleable,bright and shiny when new

but quickly oxidizes to a dull

grey. Resistant to corrosion.

Protection against

X-Ray machines.Paints, roof

coverings,

flashings.

Zinc Pure metal A layer of oxide protects it

from corrosion, bluish-

white, easily worked.

Makes brass.

Coating for steel

galvanized

corrugated iron

roofing, tanks,

buckets, rust-

proof paints




Nam

e Com

position Properties UsesTin Pure metal White and soft, corrosion

resistant.

Tinplate, making

bronze.



Metals testing Steel bar

Tensile strength

Bending



Pig iron

is the intermediate product of smelting iron ore with a high-

carbon fuel such as coke

usually with limestone as a flux

within integrated steel mills, blast furnace iron - hot metal - is

transferred directly to the steel plant in liquid form

The term pig iron arose from the old method of casting blast

furnace iron into moulds arranged in sand beds such that they

could be fed from a common runner.

The group of moulds resembled a litter of sucking pigs, theingots being called pigs and the runner the sow.



Pig ironIngots

(pigs)

runner (sow)



Iron ore

Iron ores are rocks and minerals from which metallic iron can

be economically extracted.



Blast furnace

Video 1

Video 2



Cast iron

Is derived from pig iron, and while it usually refers to gray(grey) iron

Cast iron tends to be brittle, except for malleable cast irons

It has relatively low melting point, good fluidity, castability,

excellent machinability, resistance to deformation and wearresistance

are used in pipes, machines and automotive industry parts,such as cylinder heads, cylinder blocks and gearbox cases

It is resistant to destruction and weakening by oxidation (rust)

Types Grey cast iron

White cast iron

Ductile cast iron



Cast iron



Cast iron

Video 1

Video 2



Wrought iron

is an iron alloy with a very low carbon content

alloy - is a mixture or metallic solid solution composed of two or moreelements

is tough, malleable, ductile and easily welded

A modest amount of wrought iron was used as a raw materialfor manufacturing of steel, which was mainly to produceswords, cutlery, chisels, axes and other edge tools as well assprings

items produced from wrought iron included rivets, nails, wire,chains, railway couplings, water and steam pipes, nuts, bolts,

horseshoes, handrails, straps for timber roof trusses, andornamental ironwork

They got that description because they are wrought (worked)by hand



Wrought iron form or shapes

Bar ironiron in bars, which are the usual product of the

finery forge. These might be square or flat, and flat bars might

be narrow or broad.

Rod ironcut from flat bar iron in a slitting mill to provide the

raw material for nails.

Hoop ironsuitable for the hoops of barrels, made by passing

rod iron through flat rolls.

Plate ironsheets of iron suitable for use as boiler plate.

Black platesheets of iron, perhaps thinner than plate iron,from the black rolling stage of tinplate production.

Voyage ironnarrow flat bar iron, made or cut into bars of a

particular weight.



Wrought iron



Wrought iron

Plate iron Hoop ironBar iron

Plate iron

Black plate iron



Steel

Is an alloy of iron and carbon, content between 0.2% and 2.1%

by weight: above 2.1% = cast iron

Carbon is the most common alloying material for iron, but

various other alloying elements are used, such as manganese,

chromium, vanadium, and tungsten

Steel with increased carbon content can be made harder and

stronger than iron, but such steel is also less ductile than iron.

Steel is one of the most common materials in the world, with

more than 1.3 billion tons produced annually It is a major component in buildings, infrastructure, tools,

ships, automobiles, machines, appliances, and weapons



Steel

Steelmaking - video



Steel in construction

Reinforcing steel

A rebar (short for reinforcing bar), also known as reinforcing steel,reinforcement steel, rerod, or a deformed bar, is a common steelbar

is commonly used as a tensioning device in reinforced concrete and

reinforced masonry structures holding the concrete in compression

Types

Plain bars (R)

Plain bars are round in cross section.

They are used in concrete for special purposes, such as dowels atexpansion joints, where bars must slide in a metal or paper sleeve, for

contraction joints in roads and runways, and for column spirals. They are the least used of the rod type of reinforcement because they

offer only smooth, even surfaces for bonding with concrete.

Sizes - R BAR 6mmR BAR 8mm R BAR 10mmR BAR 12mm R BAR 16mm R BAR 20mmR BAR 25mm R BAR 30mm R BAR 32mm R BAR 35mm R BAR 40mm

Length: 12m



Steel in construction

Mild steel High Yield Deformed bar (Y)

The twisted bar, for example, is made by twisting a plain, square bar cold

The spiral ridges, along the surface of the deformed bar, increase its bond

strength with concrete

is commonly used as a tensioning device in reinforced concrete

Sizes -Y BAR 10mm Y BAR 12mm Y BAR 16mm Y BAR 20mm

Y BAR 25mm Y BAR 32mm Y BAR 40mm



Steel in constructionRound bars (Y)



Steel in constructionDeformed bars (Y)



Non-ferrous metals

Non-ferrous

Lead

Copper

Aluminum

Zinc



Lead

Lead is a soft, malleable poor metal

It is also counted as one of the heavy metals

Lead has a shiny chrome-silver luster when it is melted into a

liquid

Lead is used in building construction, lead-acid batteries,

bullets and shots, weights, as part of solders, pewters, fusible

alloys and as a radiation shield

Lead, at certain exposure levels, is a poisonous substance to

animals as well as for human beings Lead is naturally present in soil and water at very low levels

Lead's physical properties of low melting point (at 621 °F),

easy malleability, corrosion resistance



Lead



Tin

Tin is a malleable, ductile and highly crystalline silvery-white

metal

This silvery, malleable poor metal is not easily oxidized in air

Is used for corrosion-resistant tin plating of steel.

Because of its low toxicity, tin-plated metal is also used for

food packaging, giving the name to tin cans, which are made

mostly of steel.

In 2006, about half of tin produced was used in solder. The

rest was divided between tin plating, tin chemicals, brass andbronze, and niche uses

This soft metal has a low melting point at 450 °F



Tin

Solder wirePewter plate

Tin plating



Zinc

The metal is hard and brittle at most temperatures but becomesmalleable between 100 and 150 °C

Above 210 °C, the metal becomes brittle again and can be pulverizedby beating

Zinc is a fair conductor of electricity

For a metal, zinc has relatively low melting (419.5 °C, 787.1 F) andboiling points (907 °C)

Its melting point is the lowest of all the transition metals aside frommercury and cadmium

Major applications of zinc include (numbers are given for the US)[89]

Galvanizing (55%) Alloys (21%)

Brass and bronze (16%)

Miscellaneous (8%)



Zinc Galvanizing (55%)

The metal is most commonly used as an anti-corrosion agent

Galvanization, which is the coating of iron or steel to protect the metalsagainst corrosion, is the most familiar form of using zinc in this way

Alloys (21%)

A widely used alloy which contains zinc is brass, in which copper isalloyed with anywhere from 3% to 45% zinc, depending upon the type of brass

Brass and bronze (16%)

Brass is generally more ductile and stronger than copper and hassuperior corrosion resistance

These properties make it useful in communication equipment, hardware,musical instruments, and water valves

Miscellaneous (8%)

Zinc oxide is widely used as a white pigment in paints, and as a catalyst inthe manufacture of rubber.

Zinc chloride is often added to lumber as a fire retardant and can be usedas a wood preservative



Zinc

Zinc oxide Zinc Zinc roof sheet

B r a s s

B r o nz e



Aluminum

Aluminium or aluminum is a silvery white member of the

boron group of chemical elements

It is not soluble in water under normal circumstances.

Aluminium is the third most abundant element (after oxygen

and silicon), and the most abundant metal, in the Earth's crust

it is found combined in over 270 different minerals, the chief

ore of aluminium is bauxite

Aluminium is remarkable for the metal's low density and for

its ability to resist corrosion due to the phenomenon of

passivation.

Structural components made from aluminium and its alloys

are vital to the aerospace industry and are important in other

areas of transportation and structural materials



Aluminum

Aluminium is a soft, durable, lightweight, ductile and malleablemetal with appearance ranging from silvery to dull gray, dependingon the surface roughness.

Aluminium is nonmagnetic and does not easily ignite.

Some of the many uses for aluminium metal are in:

Transportation (automobiles, aircraft, trucks, railway cars, marinevessels, bicycles, etc.) as sheet, tube, castings, etc.

Packaging (cans, foil, etc.)

Construction (windows, doors, building wire, etc.)

A wide range of household items, from cooking utensils to baseballbats, watches.

Street lighting poles, sailing ship masts, walking poles, etc. Outer shells of consumer electronics, also cases for equipment e.g.

photographic equipment.

Powdered aluminium is used in paint, and in pyrotechnics such assolid rocket fuels and thermite.

Sustainability of Aluminium in Buildings



Aluminum

Aluminum folding windowAluminum building wire



Aluminum testing

Video 1 Aluminum Tensile Test. YouTube

Video 2 - Tensile test of aluminum push-pull tube - YouTube

metals - complete version

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