• Muhammad Shariq Masood (IM-107)

• Muhammad Umair Akram (IM-079)

• Syed Haseeb Ahmed (IM-138)

• Javeria Haseeb (IM-307)

NED UNIVERSITY OF ENGINEERING & TECHNOLOGY

INDUSTRIAL & MANUFACTURING ENGINEERING

PROJECT OF MATERIALS ENGINEERING

(CAST IRON)

Cast Iron

Cast Iron

Cast iron is made when pig iron is re-melted in small cupola furnaces(similar to the blast furnace in designand operation) and poured into moldsto make castings. Cast Iron isgenerally defined as an alloy of Ironwith greater than 2% Carbon, andusually with more than 0.1% Silicon.

The ferrous alloy of iron containscarbon (2 - 4%), and silicon(0.5 -3.5%) is Cast Iron.

It have low ductile property

High brittle property

Low machine ability

Micro structure varies with differenttypes, usually pearlite, ferrite andaustenite.

Microstructures

It possess

Ferrite

Austenite

Pearlite

Martensite

Cementite

Iron Iron Carbon Equilibirium DiagramSteels Cast Irons

Eutectic

SpheroidsIrregular Spheroids

Malleable iron

• heat treat at 800-900ºC

• graphite in rosettes

• more ductile

• Its composition is 2.0-2.9% of carbon,

0.9-1.9% of Silicon, 0.15-1.2% of

Manganese,0.02-0.2% of Sulfur,0.02-

0.2% of phosphorous.

Graphite Flakes

Types of cast iron

• White Cast Iron.

• Gray Cast Iron.

• Ductile/Nodular Cast Iron.

• Malleable Cast Iron.

Gray iron

• graphite flakes

• weak & brittle under tension

• stronger under compression

• excellent vibrational dampening

• wear resistant

• Its composition is 2.5-4.0% of carbon, 1.0-

3.0% of Silicon, 0.2-1.0% of Manganese,

0.02-0.25% of Sulfur, 0.02-1.0% of

phosphorous. Adapted from Fig. 11.3(a), Callister 7e.

Ductile iron

• add Mg or Ce

• graphite in nodules not flakes

• matrix often pearlite - better ductility

• Its composition is 3.0-4.0% of carbon,

1.8-2.8% of Silicon, 0.2-1.0% of

Manganese, 0.01-0.03% of Sulfur, 0.01-

0.1% of phosphorous.

Adapted from Fig. 11.3(b), Callister 7e.

White iron

• <1wt% Si so harder but brittle

• more cementite

• Its composition is 1.8-3.6% of carbon,

0.5-1.9% of Silicon, 0.25-0.8% of

Manganese, 0.06-0.2% of Sulfur, 0.06-

0.2% of phosphorous.

Adapted from Fig. 11.3(c), Callister 7e. Adapted from Fig. 11.3(d), Callister 7e.

Cementite

Advantages

Good strength to weight ratio.

Lower density and higher

thermal conductivity than

steels at comparable tensile

strength levels.

Excellent machinability.

Rapid transition from design to

finished product

Excellent damping capacity,

especially in Gray Irons.

Disadvantages

Natural Or Inherent Problems

Rusting

Graphitization

COATINGS FAILURE

MECHANICAL FAILURE:

Structural Failure:

Mechanical Failure of

Connections:

Applications

Essential parts in trains, frames,suspensions, and wheels.

differential cases, bearing caps,steering-gear housings, springhangers, universal-joint yokes,automatic transmission parts,rocker arms, disc brake calipers,wheel hubs, etc...

a) Driveline yokes, b)Connecting rods, c) Dieselpumps, d) Steering-gear housing.