Carbon
Steel Types
Low carbon steel
60HRB, Plate, sheet, strip, pipes, tubes Carbon –
0.30%max
Mild steel
90HRB, Structural shapes, Carbon– 0.15 to 0.30%
Medium Carbon Steel
Carbon 0.3- 0.5%, 25HRC, Machine parts
High Carbon Steel
Carbon 0.5 to 1.0%, 40HRC, springs, railroads,
abrasion resistant
Low
Alloy Steel Types & Application
Alloying element< 10%
HSLA steels- high strength, thick comes down, better
toughness, resistant to corrosion in specific environment e.g. Corten
Pipelines, pressure vessels, penstock, offshore structures
Normally used in as rolled or normalized condition.
Alloying elements are Ni, Cu, Mo, Ti, V, and Nb.
Low
Alloy Steel
QT Steel
Furnished in heat treated condition, No further heat
treatment is required. Has high yield strength. E.g. HY80, HY100, HY130 primarily
used as plate
Application: Earthmoving equipment, armour application
(defense), pressure vessel, steel mill and mining equipment, ships, TV towers
Cr-Mo Steel
0.5 to 9% Cr, 0.5 to 1.0%Mo
Air harden able, Creep Properties, good high temperature
yield strength
Improved oxidation and corrosion resistance
Mo increases strength at high temperature
Ti, V, Nb, N2 addition increases further creep properties.
Used widely in refineries and power generating
equipment
Nickel Steel
0.5 to 9% Nickel
Good low temperature properties
Good toughness at low temperature
Cryogenic applications
Pressure vessels, storage tank in refineries,
petrochemicals, fertilizer industries
High
Alloy Steel
Alloying content > 10%
Ni-Co alloy steel, Mar aging steel (Ni), Austenitic
Manganese steel
Ultra high strength steel
Used widely for rocket motor, jaw crushers, mining
equipment, bicycle frame
Age hardening
Coated
Steel
Lower production cost
Better and more consistent product Reduced energy
usage
Easier compliance with environmental, health and
safety concerns
Coating could be metallic or paint
Protective coating or decorative Resistance welding
preferred
Stainless
& Heat Resisting Steel
Min Cr required is 10.5% for making the steel stainless.
Chromium oxide film gives the protection
High thermal coefficient
Low thermal conductivity
More distortion compared to Carbon steel
Very widely used as pressure vessels, heat exchangers
in chemical, petrochemical, fertilizer and offshore industries
Stainless
steel: Types
Martenistic --- low Cr around 13%
Ferritic --- high Cr around 17 to 26%
Austenitic --- Cr-Ni typical 18/8, 25/20
Duplex ---- high Cr and low Ni, 22 to 25 Cr, 4 to 6
Ni
Austenitic grades are 200 and 300 series, non
magnetic
Clad
Steel
To reduce cost and also having chemical corrosion
resistance
Hydro treaters, chemical, petrochemical,
Marine applications
Surfacing, hard facing, spraying
Other
Materials
Ti &Ti alloys
High strength to weight ratio
Used widely in chemical, aerospace, marine field
Good chloride resistance
Zirconium
Reactive metal used in chemical and petrochemical,
food processing
Tantalum:
Chemical equipments, corrosion resistance
Al & Al alloys: good electric and thermal conductivity,
Non magnetic. Inherent corrosion resistance, Light weight
Mg & Mg alloys
Low weight, Used in Industrial Textiles, printing
machines, material handling (gravity conveyor, grain shovel), aerospace
Cu & Cu alloys
Brass, Bronze, Cupro - Nickel
Application in water tubing, valves, fittings, heat
exchangers, chemical equipment, bearings, sprinklers
Ni & Ni alloys
Chemical and Heat resistant application like SS
Nickel, Monel, Inconel, Incoloy,
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