CPI M2U3 IRON AND STEEL

Steel

purer form of iron with lower carbon content. It can be produce from molten iron ore with blast or air (BOF), Electric furnace, Bessemer converter.

Iron

a chemical element. It is strong, hard, heavy gray metal. 5% of the Earth’s crust

Strength/Tensile strength

maximum load that it can support without yielding

Toughness/Hardness

resistance to fracture or ability to absorb energy of a material when impacted

Ductility

ability to be drawn into wires without fractures

Durability

corrosion resistance

Malleability

ability to be rolled or beaten into sheets without fracture

Weldability

capacity to be welded under specific set of fabrication and design conditions, to perform as expected during its service life

Elasticity/Elongation

deformation to an extent that the original shape can be regained when the applied load is removed.

Alloying

the process that is used to change the chemical composition of steel and improves its properties

Ni Mn Co Cu

Stabilizing austenite- increase the temperature range in which austenite exists

Cr T Mo Al Si

Stabilizing ferrite- can have effect of lowering carbon solubility

Cr T Mo

Carbide forming- increases hardness and strength

Ni Co Al

Graphitizing- decreases stability of carbides in steel promoting breakdown

Al Si Cr

Increase corrosion resistance- protects metal from deterioration

4000 years to the beginning of the iron age.

The development of steel can be traced back

Henry Bessemer

developed an effective way to use oxygen to reduce the carbon content in iron: The modern steel industry was born.

Pure iron

silvery white colored metal and is extremely lustrous.

Wrought iron

it can be heated and reheated and worked into various shapes, becomes stronger the more it is worked,

Cast iron

has higher carbon and silicon contents than steel.

White cast iron

having characteristic white crystalline fracture surface. It is very often used for its excellent resistance to wear and abrasion.

Gray cast iron

The fracture surface appears gray because of the predominance of exposed graphite. It has very good properties for use in vibration damping or moderate thermal shock applications.

Ductile cast iron

It is also known as nodular iron or spheroidal graphite cast iron.

Malleable cast iron

The ductility and toughness of _________ ____ ____falls between that of ductile cast iron and gray cast iron.

Chilled iron

It is white iron that has been produced by cooling very rapidly through the solidification temperature range.

Mottled iron

It is an area of the casting that solidifies at a rate intermediate between those for chilled and gray iron, and which exhibits microstructural and fracturesurface features of both types.

Compacted graphite cast iron

It is also known as vermicular iron. It is characterized by graphite that is interconnected within eutectic cells, as is the flake graphite in gray iron. The major applications are disc-brake rotors and diesel-engine heads.

High-alloy graphitic iron

It is used primarily for applications requiring corrosion resistance or a combination of strength and oxidation resistance.

Pig iron

an intermediate product of a steel plant

Basic grade

pig iron has less than 1.0 % silicon, under 1 % manganese, and trace amounts of sulphur and phosphorous. This type of pig iron is mainly used for steel making.

Foundry grade

This type of pig iron is being used in iron foundries and contains higher silicon.

Direct reduced iron

produced by the reduction of iron ore (in the form of lumps or pellets) by either non-coking coal or a reducing gas produced by reforming of natural gas is also known as sponge iron..

Carbon steel

contain trace amounts of alloying elements and account for 90% of total steel production.

Low Carbon Steels/Mild Steels

contain up to 0.3% carbon

Medium Carbon Steels

0.3 – 0.6% carbon

High Carbon Steels

contain more than 0.6% carbon

Stainless steel

generally contain between 10-20% chromium as the main alloying element and are valued for high corrosion resistance.

Austenitic steel

are non-magnetic and non-heat-treatable, and generally contain 18% chromium, 8% nickel and less than 0.8% carbon. often used in food processing equipment, kitchen utensils, and piping.

Ferritic steel

contain trace amounts of nickel, 12-17% chromium, less than 0.1% carbon, along with other alloying elements, such as molybdenum, aluminum or titanium. These magnetic steels cannot be hardened by heat treatment but can be strengthened by cold working.

Martensitic steel

These magnetic and heat-treatable steels are used in knives, cutting tools, as well as dental and surgical equipment.

Tool steel

contain tungsten, molybdenum, cobaltand vanadium in varying quantities to increase heat resistance and durability, making them ideal for cutting and drilling equipment.

Magnetite

acquired its name through its magnetic properties. When it is scratched against an uncolored surface a black streak is formed.

Hematite

has acquired its name from the blood red streak that is formed when scratched.

Iron and steel scrap

used as a secondary raw material, both for scrap-based and orebased steel production.

Internal scrap

is scrap that falls to the floor within the plants during steel production and that is directly recovered for the production process.

Engineering workshop scrap

is the scrap that arises during the working of steel in workshops, within the construction industry, on bridge building etc.

Scrap metal collection

is the scrap collected from end-of-life products e.g. on demolition of structures and installations and from households. The scrap may include everything from bridge beams to household utensils.

Coke

act as a physical support material for the blast furnace charge, to raise the carbon content in the iron and to supply energy.

Limestone

used as a slag former in the iron and steelmaking process.

Slag

serves to bind substances which are not desired in the steel being produced. This enables one to control the composition and thereby give the steel improved properties.

Manganese

Desulpherizing (sulphur causes steel to crack) and as alloying element for strength and toughness

Silicon

Used to de-oxidize steel

Nickel

Anti-corrosion (nickel content in high quality stainless steel 8-10%)

Chromium

Resistance to corrosion, temperature and wear (used in stainless steel (average content 18%)

Basic Oxygen Steel making (BOS) and Electric Ark Furnaces (EAF)

two main methods for making steel

Basic Oxygen Steel making (BOS)

involve adding scrap steel to the molten iron when in the furnace.

Electric Ark Furnaces (EAF)

recycled steel is fed into an electrical ark furnace along with the molten iron which is then heated to around 1650 degrees Celsius in order to convert it into high-grade steel.

SECONDARY STEELMAKING

Next the newly formed molten steel needs to be adjusted to make the perfect steel composition. This is done by either manipulating the temperature and/or removing certain elements

CONTINUOUS CASTING

to pour it into cooled moulds. This causes the metal to cool quickly. Once cooled the metal is then cut into desired lengths depending upon the application.

First forming

the initial shapes of slabs, blooms, and billets are formed into their various shapes usually by hot rolling.

MANUFACTURING, FABRICATION AND FINISHING

secondary forming techniques give the steel its final shape and properties

CONSTRUCTION

TRANSPORT

ENERGY

PACKAGING

APPLIANCES AND INDUSTRY

USES AND APPLICATIONS

Organic pollutants

Water

Dust

Air

ENVIRONMENTAL IMPACT