IB Design Technology Topic A3.1.2 Classification by Source Revision Notes (SL/HL)

IB Design Technology Topic A3.1.2 Classification by Source Revision Notes (SL/HL) | RevisionDojo

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Source: Every Material Is Either Natural or Human-Made

Materials can be classified by their source or origin: either natural, taken from the living or geological world, or human-made, synthesised or processed by people.
This is a different lens from the property families in A3.1.1, which asked what a material does rather than where it came from.
Source matters because it drives a material's properties, its environmental impact and its suitability for a given product.

Timbers: Renewable and Workable, but Vulnerable to Moisture

Definition

Timber (lumber)

Timber is wood that has been harvested from trees and processed for use in manufacturing, construction, and carpentry. It is typically classified into softwoods (from coniferous trees) and hardwoods (from deciduous trees), based on the type of tree it comes from.

Timber is a natural material sourced from trees, valued for being renewable and for its strength and appearance.
It has a good strength-to-weight ratio, so it carries useful load without being heavy.
It can be machined, sanded and finished easily, which keeps tooling simple and cheap.
It is naturally insulating, both thermally and acoustically.
Left untreated, it is attacked by moisture, insects and rot, which is the trade-off you accept for choosing it.

Type	Hardwoods	Softwoods
Source	Trees with broad leaves (deciduous trees)	Trees with needles (coniferous trees)
Growth	Grows slowly – denser, stronger wood	Grows faster – less dense, easier to work with
Grain	Usually tighter grain, rich colour and texture	Typically lighter grain, more uniform
Examples	Oak, Mahogany, Beech, Walnut	Pine, Cedar, Spruce, Fir
Cost	Generally more expensive due to slower growth	Generally cheaper and more sustainable

Example

Hardwoods are typically used for:
- High-quality furniture, flooring and doors.
- Decorative finishes, veneers and musical instruments.
- Tool handles, where toughness matters.
Softwoods are typically used for:
- Structural construction such as beams and roof trusses.
- General DIY work, shelving, interior trim and cladding.

Sourcing Timber Responsibly

Softwoods grow faster, which makes them the more sustainable choice for mass production.
Many hardwoods come from tropical regions, so they must be sourced responsibly rather than simply bought on price.
Forest Stewardship Council (FSC) certified timber comes from managed forests that protect the environment and support local communities.

Metals: Extracted From Ore, Sorted by Iron Content

Metals occur naturally but are extracted from ores in the earth's crust, so they are natural in origin yet heavily processed before use.
They are good conductors of heat and electricity, and are generally strong, durable and malleable.
Metals are classified by their iron content:
1. Ferrous metals contain iron, which makes them strong but prone to rust.
2. Non-ferrous metals contain no iron, so they resist corrosion.
Metals are often combined into alloys to improve performance for a specific job, such as adding chromium to steel to make it stainless.

Classification	Ferrous Metals	Non-Ferrous Metals	Alloys
Examples	Mild steel, Cast iron	Aluminium, Copper, Zinc	Brass, Stainless steel
Key Properties	Strong, tough, magnetic, can rust	Lightweight, corrosion-resistant, good conductors	Enhanced properties (e.g. rust resistance, strength)
Common Uses	Construction, tools, car bodies	Wiring, cans, roofing, plumbing	Cutlery, instruments, decorative fittings

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Source: Every Material Is Either Natural or Human-Made

Materials can be classified by their source or origin: either natural, taken from the living or geological world, or human-made, synthesised or processed by people.
This is a different lens from the property families in A3.1.1, which asked what a material does rather than where it came from.
Source matters because it drives a material's properties, its environmental impact and its suitability for a given product.

Timbers: Renewable and Workable, but Vulnerable to Moisture

Definition

Timber (lumber)

Timber is a natural material sourced from trees, valued for being renewable and for its strength and appearance.
It has a good strength-to-weight ratio, so it carries useful load without being heavy.
It can be machined, sanded and finished easily, which keeps tooling simple and cheap.
It is naturally insulating, both thermally and acoustically.
Left untreated, it is attacked by moisture, insects and rot, which is the trade-off you accept for choosing it.

Type	Hardwoods	Softwoods
Source	Trees with broad leaves (deciduous trees)	Trees with needles (coniferous trees)
Growth	Grows slowly – denser, stronger wood	Grows faster – less dense, easier to work with
Grain	Usually tighter grain, rich colour and texture	Typically lighter grain, more uniform
Examples	Oak, Mahogany, Beech, Walnut	Pine, Cedar, Spruce, Fir
Cost	Generally more expensive due to slower growth	Generally cheaper and more sustainable

Example

Hardwoods are typically used for:
- High-quality furniture, flooring and doors.
- Decorative finishes, veneers and musical instruments.
- Tool handles, where toughness matters.
Softwoods are typically used for:
- Structural construction such as beams and roof trusses.
- General DIY work, shelving, interior trim and cladding.

Sourcing Timber Responsibly

Softwoods grow faster, which makes them the more sustainable choice for mass production.
Many hardwoods come from tropical regions, so they must be sourced responsibly rather than simply bought on price.
Forest Stewardship Council (FSC) certified timber comes from managed forests that protect the environment and support local communities.

Metals: Extracted From Ore, Sorted by Iron Content

Metals occur naturally but are extracted from ores in the earth's crust, so they are natural in origin yet heavily processed before use.
They are good conductors of heat and electricity, and are generally strong, durable and malleable.
Metals are classified by their iron content:
1. Ferrous metals contain iron, which makes them strong but prone to rust.
2. Non-ferrous metals contain no iron, so they resist corrosion.
Metals are often combined into alloys to improve performance for a specific job, such as adding chromium to steel to make it stainless.

Classification	Ferrous Metals	Non-Ferrous Metals	Alloys
Examples	Mild steel, Cast iron	Aluminium, Copper, Zinc	Brass, Stainless steel
Key Properties	Strong, tough, magnetic, can rust	Lightweight, corrosion-resistant, good conductors	Enhanced properties (e.g. rust resistance, strength)
Common Uses	Construction, tools, car bodies	Wiring, cans, roofing, plumbing	Cutlery, instruments, decorative fittings

Definition

Paywall

(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Note

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

Tip

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
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A. Design in theory8 subtopics

B. Design in practice8 subtopics

C. Design in context8 subtopics

IB Design Technology Topic A3.1.2: Classification by Source Notes

A. Design in theory8 subtopics

B. Design in practice8 subtopics

C. Design in context8 subtopics

Source: Every Material Is Either Natural or Human-Made

Timbers: Renewable and Workable, but Vulnerable to Moisture

Sourcing Timber Responsibly

Metals: Extracted From Ore, Sorted by Iron Content

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

Source: Every Material Is Either Natural or Human-Made

Timbers: Renewable and Workable, but Vulnerable to Moisture

Sourcing Timber Responsibly

Metals: Extracted From Ore, Sorted by Iron Content

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account