40 inventive principles / #37

#37 Thermal expansion

What it says

• Use the expansion or contraction of materials with temperature.
• Combine materials with different expansion rates.

Examples

Software

Capacity that grows with demand and shrinks after it.

Business

Teams that grow and shrink with the project phase.

Engineering

Bimetallic strips in thermostats.

Everyday life

Run a stuck jar lid under hot water.

Where the matrix suggests it

The classic contradiction matrix suggests Thermal expansion in 60 of its 1,248 filled cells. Most often for these conflicts:

• Improving Stress or pressure worsens Loss of time
• Improving Stability of the object's composition worsens Length of stationary object
• Improving Loss of time worsens Stress or pressure
• Improving Length of stationary object worsens Stability of the object's composition
• Improving Volume of stationary object worsens Productivity
• Improving Force worsens Loss of time
• Improving Force worsens Ease of manufacture
• Improving Force worsens Difficulty of detecting and measuring