Selection of Materials (Junior Cert Applied Technology): Revision Notes
📚 Revision Notes
Material Selection
Overview
- Choosing materials is crucial in product design and making. It ensures quality and keeps things eco-friendly.
- Picking the right materials impacts working, looks, and safety.
Definitions
- Choosing Materials: Picking materials based on what they can do, their cost, availability, and how eco-friendly they are.
- Mechanical Properties: How a material behaves under stress, like strength and hardness.
- Thermal Stability: If a material can keep its properties at high temperatures.
- Sustainability: Materials that meet today's needs without harming future needs.
- Ashby Chart: A graph that helps compare material properties for easy selection.
- Decision Matrix: A tool to evaluate and rank options based on certain criteria.
Importance of Material Choice
- Ensures products are strong, work well, and save money.
- Impacts the whole product lifecycle and its eco-friendly aspect.
- Different materials, like metal, wood, and plastics affect design differently.
Main Considerations for Choosing Materials
- Important points to consider:
- Mechanical Properties
- Thermal Stability
- Cost
- Availability
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Comparing materials:
- Metals: Strong, heat resistant.
- Plastics: Cost-saving, flexible.
- Ceramics: Heat resistant but can break.
How Material Properties Affect Design
- Material properties guide design choices.
- For example, metal's ductility allows complex designs, and some plastics are good for electronics because they insulate electricity.
- Aluminium is used in planes because it is light.
- Carbon fibre is popular in cars for its strength and lightness.
Tools and Methods for Picking Materials
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- Ashby chart: Shows properties like density and strength for easy comparison.
- Decision matrices help score and choose materials.
Examples From Various Industries
- Cars: Focus on aluminium's light weight and recyclability for eco-friendliness.
- Planes: Composites are chosen for strength and saving fuel.
- Electronics: Plastics are light and insulate well.
Challenges and Mistakes
chatImportant
- Challenges include:
- Ignoring future costs.
- Choosing wrong materials for certain conditions.
- Balancing performance and cost.
- Mistakes:
- Overlooking sustainability.
- Not considering environmental effects.
Summary
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- Wise material choice improves product eco-friendliness and lifespan.
- Key points: mechanical properties, thermal stability, cost, availability.
- Tools like Ashby charts make picking materials easier.
- Using Ashby charts and decision matrices ensures each material choice meets performance goals and is eco and cost-wise.
- Material needs differ in industries, focusing on both function and eco-responsibility.