Ferrous and Non-Ferrous Metals and Wood Properties

Ferrous Metals

• Ferrous metals: Cast iron, steel, iron.
• Non-ferrous metals: Copper, zinc, aluminum, tin, bronze, brass.
• Alloys: Mixtures of metals.

Iron and Steel Classification

• Pure iron: Soft and fragile; typically mixed with carbon to improve utility.
• Steel: Contains 0.1% to 2% carbon. It is very hardy and tenacious.
• Cast iron: Contains 2% to 4% carbon. It is fragile but very hard.

Cast Iron Applications

Used for objects that do not require high impact resistance, such as radiators and lamps.

Stainless Steel Composition

Made of carbon, chromium, nickel, and iron.

Metal Production

• Obtaining cast iron: Derived from iron ores (limonite, siderite, magnetite, pyrite, hematite) in a blast furnace. The ore contains useful metal and waste material (gangue).
• Procurement of steel: Cast iron from the furnace contains excess carbon, which must be reduced to produce steel.

Other Metals

• Copper: A good conductor, malleable, and ductile. Used for pipes, wires, and electrical components.
• Brass: An alloy of copper and zinc. Harder than copper with a gold-like color; used for decoration, door knobs, and musical instruments.

Wood Anatomy and Properties

Trunk Structure

• Bark: The outermost layer that protects the tree.
• Liber: The layer responsible for transporting sap.
• Sapwood: Young, whitish, and less dense wood.
• Heartwood: Mature wood that has reached its maximum development.

Composition and Properties

Wood is composed of cellulose, lignin, starch, and sugar. It is flammable, resistant to compression, porous, and absorbs moisture.

Wood Procurement Process

1. Cutting trees.
2. Debarking and removing branches.
3. Transport to the sawmill.
4. Processing (chopping for lumber or crushing for paper/artificial wood).
5. Drying (natural or artificial).

Types of Wood

• Hardwoods: Generally deciduous trees. Hard and dark (e.g., oak, walnut); used for furniture.
• Softwoods: Generally evergreen trees. Less dense and light in color (e.g., pine, fir); used for boxes and shelves.
• Artificial Wood: Materials derived through transformation processes, including veneer, particle board, plywood, MDF, and melamine.

Important Tree Species

Mahogany: A very hard, reddish wood used for high-quality furniture, primarily sourced from Africa.