Malleable cast iron is produced by heat treatment of white cast iron.

Heat treatment converts combined carbon into small graphite particles, improving ductility.

Definition

Malleable Cast Iron

Malleable cast iron is a type of cast iron produced by annealing white cast iron to obtain improved ductility and toughness.

Production Process

Steps involved:

1. Start with white cast iron.

2. Heat it in a furnace for long duration (around 800–900°C).

3. Carbon changes into temper carbon (graphite clusters).

Properties

Important properties:

• Good ductility

• Good toughness

• Good machinability

• Higher strength than grey cast iron

Uses

Malleable cast iron is used in:

• Pipe fittings

• Automobile parts

• Agricultural equipment

• Hand tools

Exam Points

• Produced from white cast iron

• Carbon form → temper carbon

• More ductile and tough