Ferrous Metals (Junior Cert Wood Technology): Revision Notes

Ferrous Metals

Overview of Ferrous Metals

• Ferrous metals are primarily composed of iron.

• They play a critical role in construction and manufacturing, particularly in materials technology.

• Compared to wood, ferrous metals provide enhanced strength and durability.

  

Definitions

• Ferrous Metal: Contains iron, which typically makes them magnetic and susceptible to rusting.
• Alloy: A mixture of metals, with one being iron in ferrous alloys.
• Oxidation: Interaction of ferrous metals with oxygen, causing rust and potential structural weakening.

Composition of Ferrous Metals

• Typically consist of high iron content.
• Key alloying element is carbon, which differentiates various types of ferrous metals.

Ferrous Metal	Typical Composition
Cast Iron	Iron, 2-4% Carbon
High Carbon Steel	Iron, 0.6-1.5% Carbon
High Speed Steel	Iron, high carbon, tungsten
Stainless Steel	Iron, low carbon, chromium, nickel

Properties of Cast Iron

• Exhibits hardness and brittleness but is highly machinable.
• Carbon content in cast iron ranges from 2-4%, greatly influencing its strength and wear resistance.

Key Applications of Cast Iron

• Gates: Durable and easily machined for intricate designs.
• Railings: Aesthetic and durable with ornate designs.
• Cookware: Provides even heat distribution due to thermal conductivity.

Types of Steel

• Steel types differ by carbon content and additional elements:

High Carbon Steel

• Contains high carbon; utilised in cutting tools and dies for enhanced hardness.

High Speed Steel

• Used in high-speed machining tools due to its robustness.

Stainless Steel

• Known for corrosion resistance, used in cutlery, kitchen appliances, and architectural elements.

Applications of Steel Types

• High Carbon Steel: Applied in tools like chisels and saws.
• High Speed Steel: Used for drill bits and other robust tools.
• Stainless Steel: Common in household items like sinks, cutlery, and kitchen appliances due to rust resistance.