Sl. No.

Application

Desired Properties

Composition (% )

1

Rail steel

Strength, ductility, impact and fatigue strength

C - 0.4 to 0.6 Mn and

Cr - upto 1

2

Spring steel (tension compression, torsion)

Good elongation high elastic limit (20 to 30%, 1200-1400 MPa). Good surface finish for fatigue strength

(a) C - 0.6, Mn - 0.9, Si - 2.0

(b) C - 0.5, Mn - 0.8, Cr - 1.0, V - 0.15

(c) C - 0.5, Ni - 0.9, Cr - 0.5, Ni - 0.6, Mo - 0.2

3

Structural steel (bridges, building, cars, gears, clutches, shafts)

High strength, toughness, high temperature strength, corrosion resistance

Wide range of alloy steels containing several alloying elements

4

Weldable steel for welded structures

Weldability, high resistance to atmospheric corrosion, resistance to brittle fracture

C - 0.15 to 0.3 with some

Cu and V

5

Concrete reinforcing steel

Bend 90o - 180o, tor-steel with ribs for greater surface area.

Elongation = 16%, UTS = 500-650 MPa, Y. S. = 35 MPa.

Elongation = 13%,

UTS = 600 MPa, Y. S. = 350 MPa

C - 0.3 to 0.4, Mn - 0.5 to 0.8

C - 0.45 to 0.6, Mn - 0.7 to 1.1

6

High speed steel for cutting tools

Resist temperature upto

550-600oC. Cutting tools requiring high hardness at working temperature 18 : 4 : 1 steel and

6 : 5 : 4 : 2 steel

C - 0.8, W - 18, Cr - 4, V - 1,

C - 0.8, W - 6,

Mo - 5, Cr - 4, V - 2

7

Creep resisting steel

Application in pipelines upto

400-550oC. Other parts upto

550oC

Mo - 0.4 to 6

V - 0.25 to 1.0

Cr - upto 6.0, C - low

8

Hadfield Mn steel, excavating and crushing m/c. rail road crossing, oil well, cement, mining industries. Used as casting and hot rolled

Resistance to abrasion and shock, high toughness strength and ductility

C - 1 to 1.4,

Si - 0.3 to 1.0, Mn - 10 to 14

9

High strength low alloy steel (HSLA) for automotive parts

High strength/weight ratio. Balanced properties such as toughness, fatigue strength, weldability and formability

C - 0.07 to 1.3, Ti, V, Al, Co less than 0.5

10

Ball bearing steel

Rolling element, inner and outer races. High hardness

61-65 Rc high fatigue strength

C - 0.9 to 1.1, Cr - 0.6 to 1.6, Mn - 0.2 to 0.4