Report on Iron And Steel

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Iron Introduction:

Iron is a chemical element with the

symbol Fe (from Latin: ferrum) and atomic number

26. It is a metal in the first transition series.

Oxidation state:

Like other group 8 elements, iron

exists in a wide range of oxidation states, −2 to +6,

although +2 and +3 are the most common.

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Continued…

Pure iron is soft (softer than aluminum), but is unobtainable by smelting. The material is significantly hardened and strengthened by impurities, such as carbon, from the smelting process.

History:

Iron metal has been used since ancient times,though copper alloys, which have lower meltingtemperatures, were used first in history. It is Discoveredsince 5000BC.

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Continued… Carbon Contents In Iron:

. A certain proportion of carbon (between 0.002% and 2.1%) produces steel, which may be up to 1000 times harder than pure iron.

Crude iron metal is produced in blast furnaces, where ore is reducedby coke to pig iron, which has high carbon content.

Iron chemical compounds, which include ferrous and ferriccompounds, have many uses. Iron oxide mixed with aluminumpowder can be ignited to create a termite reaction, used in weldingand purifying ores. It forms binary compounds with the halogens andthe chalcogens. Among its organ metallic compounds is ferrocene,the first sandwich compound discovered

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Characteristics

Mechanical Properties:

Mechanical properties can

be determined the variety of test,

1. Brinell test,

2. Rockwell test and

3. The Vickers hardness test

The mechanical properties of iron are significantly

affected by the sample's purity,

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Name, symbol, Atomic Number iron, Fe, 26

Element category transition metal

Group, period, block 8, 4, d

Standard atomic weight 55.845(2)

Electron configuration[Ar] 3d6 4s2

2, 8, 14, 2

Phase solid

Density (near r.t.) 7.874 g·cm−3

Liquid density at m.p. 6.98 g·cm−3

Melting point 1811 K2800 °F 1538 °C, ,

Boiling point 5182 °F 2862 °C, 3134 K,

Heat of fusion 13.81 kJ·mol−1

Heat of vaporization 340 kJ·mol−1

Molar heat capacity 25-10·mol−1·K−1

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Characteristics Phase diagram and allotropes:

Iron represents an example of allotropy in a metal.

There are at least four allotropic forms of iron, known

as α, γ, δ, and ε.

As molten iron cools it crystallizes at 1538 °C into its

δ allotrope, which has a body-centered cubic (bcc)

crystal structure. As it cools further to 1394 °C, it

changes to its γ-iron allotrope, a face-centered cubic

(fcc) crystal structure.

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Continued… At 912 °C and below, the crystal structure again

becomes the bcc α-iron allotrope, or ferrite. Finally, at

770 °C (the Curie point, Tc) iron becomes magnetic.

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Characteristics Isotopes:

Naturally occurring iron consists of four stable isotopes:

5.845% of 54Fe,

91.754% of 56Fe,

2.119% of 57Fe,

0.282% of 58Fe.

Of these stable isotopes, only 57Fe has a nuclear spin (−1/2). The nuclide 54Fe is predicted to undergo double beta decay.

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Iso NA half-life DM DE (MeV) DP

54Fe 5.8%>3.1×1022

y(β+β+) 0.6800 54Cr

55Fe Syn 2.73 y Ε 0.231 55Mn

56Fe 91.72% 56Fe is stable with 30 neutrons

57Fe 2.2% 57Fe is stable with 31 neutrons

58Fe 0.28% 58Fe is stable with 32 neutrons

59Fe Syn 44.503 d β− 1.565 59Co

60Fe syn 2.6×106 y β− 3.978 60Co

Characteristics Nucleosynthesis:

According to big bang theory, Iron is

created by extremely large, extremely hot (over 2.5

billion Kelvin) stars through the silicon burning

process. It is the heaviest stable element to be

produced in this manner.

Supernova:

Supernovas also create additional forms of

stable iron via the r-process.

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Characteristics Occurrence:

Iron is the sixth most abundant elementin the Universe, and the most common refractoryelement. It is formed as the final exothermic stage ofstellar nucleosynthesis, by silicon fusion in massivestars.

It makes up about 5% of the Earth's crust, both theEarth's inner and outer core are believed to consistlargely of an iron-nickel alloy constituting 35% of themass of the Earth as a whole.

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Chemistry and Compounds

Iron forms compounds mainly in the +2 and +3 oxidationstates. Traditionally, iron(II) compounds are calledferrous, and iron(III) compounds ferric.

Binary compounds:

The most common are iron (II, III) oxide (Fe3O4), and iron(III) oxide (Fe2O3).

Fe + 2 HX → FeX2 + H2

Fool’s Gold:

. The best known sulfide is iron pyrite (FeS2), also known as fool's gold owing to its golden luster.

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Continued… Coordination and Organometallic compounds:

Several cyanide complexes are known. The most famous example is Prussian blue, (Fe4(Fe[CN]6)3).

Potassium ferricyanide and potassium ferrocyanide are also known; the formation of Prussian blue upon reaction with iron (II) and iron (III) respectively forms the basis of a "wet" chemical test.

Ferrocene is an extremely stable complex. The first sandwich compound, it contains an iron(II) center with two cyclopentadienyl ligands bonded through all ten carbon atoms.

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History of Iron Wrought Iron:

Iron objects of great age are much rarer than

objects made of gold or silver due to the ease of corrosion of

iron. Beads made from meteoric iron in 3500 BC Wrought

iron is an iron alloy with a very low carbon (0.1 to 0.25)

content in contrast to cast iron, and has fibrous inclusions,

known as slag up to 2% by weight.

Cast iron:

Cast iron was first produced in China during 5th

century BC, but was hardly in Europe until the medieval

period.

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Continued…Cast iron was used in ancient China for warfare, agriculture, and architecture. During the medieval period, means were found in Europe of producing wrought iron from cast iron (in this context known as pig iron) using finery forges.

Steel:

Steel was first produced in antiquity by using a bloomer. Blacksmiths in Luristan in western Iran were making good steel by 1000 BC. Wootz steel by India and Damascus steel by China were developed around 300 BC and 500 AD.

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Industrial Production The production of iron or steel is a process containing two

main stages. The first stage is to produce pig iron in a blast

furnace. The second is to make wrought iron or steel from pig

iron by a further process.

Blast Furnace:

90 % of all mining of metallic ores is for the

extraction of iron. iron ores hematite (nominally Fe2O3)

magnetite (Fe3O4).

2 C + O2 → 2 CO

Fe2O3 + 3 CO → 2 Fe + 3 CO2

2 Fe2O3 + 3 C → 4 Fe + 3 CO2

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Continued… Isolation:

Small amounts of pure iron can be made

through the purification of crude iron with carbon

monoxide. The intermediate in this process is iron

pentacarbonyl, Fe(CO)5. The carbonyl decomposes on

heating to about 250°C to form pure iron powder.

Fe + CO → Fe(CO)5 (250°C) → Fe + 5CO

2Fe2O3 + 3C → 4Fe + 3CO2

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Continued… Direct Iron Reduction:

"Direct iron reduction" reduces

iron ore to a powder called "sponge" iron or "direct"

iron that is suitable for steelmaking.

2 CH4 + O2 → 2 CO + 4 H2

Fe2O3 + CO + 2 H2 → 2 Fe + CO2 + 2 H2O

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Application Metallurgy:

Iron is the most widely used of all the metals,

accounting for 95% of worldwide metal production. Its low

cost and high strength make it indispensable in engineering

applications such as the construction of machinery and

machine tools, automobiles etc .

Pure iron is quite soft, it is most commonly combined with

alloying elements to make steel.

Pig iron is not a saleable product but it can be converted into

steel and wrought iron.

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Continued… Iron Compounds:

Iron compounds are pervasive in industry as

well being used in many niche uses. Iron catalysts are

traditionally used in the Haber - Bosch process for the

production of ammonia and the Fischer-Tropsch process for

conversion of carbon monoxide to hydrocarbons for fuels and

lubricants.

Powdered iron in an acidic solvent was used in the Bechamp

reduction the reduction of nitrobenzene to aniline.

There are many compounds of Iron that are used in daily life.

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Continued… Biological Role:

Iron is abundant in biology. Iron-proteins

are found in all living organisms, ranging from the

evolutionarily primitive Achaea to humans.

The color of blood is due to the hemoglobin, an iron-

containing protein. As illustrated by hemoglobin, iron is

often bound to cofactors, e.g. in hems.

Iron is a necessary trace element found in nearly all living

organisms. Iron-containing enzymes and proteins.

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Continued… Bioinorganic compounds:

The most commonly known and

studied "bioinorganic" compounds of iron (i.e., iron

compounds used in biology) are the heme proteins: examples

are hemoglobin, myoglobin, and cytochrome P450.

Health and diet:

Iron is pervasive, but particularly rich sources

of dietary iron include red meat, lentils, beans, poultry, fish,

leaf vegetables, watercress, tofu, chickpeas, black-eyed peas,

blackstrap molasses, fortified bread, and fortified breakfast

cereals.

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Continued… Toxicity:

It is occurs when there is free radical of ferrous

iron atom. It is very toxic and could damage DNA,

proteins, lipids, and other cellular components.

Thus, iron toxicity occurs when there is free iron

in the cell, which generally occurs when iron levels

exceed the capacity of transferring to bind the iron.

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Steel Introduction:

Steel is an alloy of iron and a small amount

of carbon. Carbon is the primary alloying element, and its

content in the steel is between 0.002% and 2.1% by

weight.

Additional elements may be present in steel:

manganese, phosphorus, sulfur, silicon, and traces of

oxygen, nitrogen and aluminium.

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Material properties Iron is found on Earth in the form of Magnetite and Hematite

and then we pure by removing the Oxygen from them.

Small quantities of iron were smelted in ancient times, in the

solid state, by heating the ore buried in a charcoal fire and

welding the metal together with a hammer, squeezing out the

impurities.

Smelting results in an alloy (pig iron) that contains too much

carbon to be called steel.

To inhibit corrosion, at least 11% chromium is added to steel so

that a hard oxide forms on the metal surface

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Continued… Sulfur, nitrogen, and phosphorus make steel more

brittle.

The density of steel varies based on the alloying

constituents but usually ranges between

7,750 and 8,050 kg/m3

7.75 and 8.05 g/cm3

At room temperature, the most stable form of iron is

the body-centered cubic (BCC) structure called ferrite

or α-iron.

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Heat Treatment: The most common are annealing and quenching and

tempering.

Types of Steel

Steel is basically an alloy of iron and carbon with asmall percentage of other metals such as nickel,chromium, aluminum, cobalt, molybdenum, tungsten etc.

Carbon Steels:

Steel is considered to be carbon steel whenno minimum content is specified or required forchromium, cobalt, columbium [niobium], molybdenum,nickel, titanium, tungsten, vanadium or zirconium.

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Continued… Low-carbon :

Steels contain up to 0.30% C.

Medium-carbon :

Steels are similar to low-carbon steels except that the carbon ranges from 0.30 to 0.60% and the manganese from 0.60 to 1.65%.

Ultrahigh-carbon :

Steels are experimental alloys containing 1.25 to 2.0% C

High-Strength Low-Alloy Steels:

The HSLA steels have low carbon contents (0.05-0.25% C) in order to produce adequate formability and weld ability, and they have manganese contents up to 2.0%.

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Low-alloy Steels Low-alloy steels constitute a category of ferrous materials that

exhibit mechanical properties superior to plain carbon steels as the result of additions of alloying elements such as nickel, chromium, and molybdenum. Total alloy content can range from 2.07% up to levels just below that of stainless steels, which contain a minimum of 10% Cr.

As with steels in general, low-alloy steels can be classified according to:

Chemical composition, such as nickel steels, nickel-chromium steels, molybdenum steels, chromium-molybdenum steels

Heat treatment, such as quenched and tempered, normalized and tempered, annealed.

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Continued… Low-carbon quenched and tempered steels:

Combine high yield strength (from 350 to 1035 MPa) andhigh tensile strength with good notch toughness, ductility,corrosion resistance, or weld ability.

Medium-carbon ultrahigh-strength steels:

They are structural steels with yield strengths that canexceed 1380 MPa.

Bearing steels:

It used for ball and roller bearing applications arecomprised of low carbon (0.10 to 0.20% C) case-hardenedsteels and high carbon (-1.0% C) through-hardened steels.

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Continued… Chromium-molybdenum heat-resistant steels:

It contain 0.5 to 9% Cr and 0.5 to 1.0% Mo. The carbon content is usually below 0.2%.

History Of Steel Making

Ancient steel:

Steel was known in antiquity, and may have been produced by managing bloomeries, or iron-smelting facilities, in which the bloom contained carbon.

Steel was produced in large quantities in Sparta around 650BC.

Wootz steel and Damascus steel:Wootz steel was produced in India

by about 300 BC However; the steel was an old technology in India when King Porus presented a Steel sword to the Emperor Alexander in 326 BC

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Modern Steel Making Originally using charcoal, modern methods use coke, which

has proven more economical.

Processes Starts from Bar Iron:

In these processes pig iron was "fined" in a finery forge to produce bar iron (wrought iron), which was then used in steel-making.

The production of steel by the cementation process was described in a treatise published in Prague in 1574 and was in use in Nuremberg from 1601.

Process Starts from Pig Iron:

The modern era in steelmaking began with the introduction of Henry Bessemer's Bessemer process in 1855, the raw material for which was pig iron.

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Steel Industry: The steel industry is often considered an indicator of economic

progress.

In 1980, there were more than 500,000 U.S. steelworkers. By

2000, the number of steelworkers fell to 224,000.

Between 2000 and 2005, world steel demand increased by 6%.

Shanghai Baosteel Group Corporation and Shagang Group.

ArcelorMittal is however the world's largest steel producer.

2008, the steel industry faced a sharp downturn that led to

many cut-backs.

ThyssenKrupp offered the plants for sale at under $4 billion.

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Contemporary Steel: High strength low alloy steel has small additions (usually

< 2% by weight) of other elements, typically 1.5%

manganese, to provide additional strength for a modest

price increase.

Low alloy steel is alloyed with other elements, usually

molybdenum, manganese, chromium, or nickel, in

amounts of up to 10% by weight to improve the harden

ability of thick sections.

Stainless steels contain a minimum of 11% chromium,

often combined with nickel, to resist corrosion.

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Uses: Iron and steel are used widely in the construction of roads, railways, other

infrastructure, appliances, and buildings.

Most Large Structure buildings contain the skeleton of steel, such as

stadiums and skyscrapers, bridges, and airports, are supported by a steel

skeleton

Other common applications

include shipbuilding, pipelines, mining, offshore

construction, aerospace, white goods (e.g. washing machines), heavy

equipment such as bulldozers, office furniture, steel wool, tools,

and armour in the form of personal vests or vehicle armour (better known

as rolled homogeneous armour in this role).

So Iron and Steel have many application

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