IB Design Technology 4.1.1 Role of Material Properties in Design Notes

Expanding Material Choices, Complexity of Selection, and Ethical Considerations

Imagine you’re a designer tasked with creating a portable, lightweight, and durable water bottle. You need a material that can withstand regular use, resist cracking, and appeal to consumers visually. Should you choose stainless steel for its strength, glass for its purity, or a polymer like PET for its lightweight properties? Now, add to this the consideration of environmental impact, how recyclable is the material? What about its carbon footprint during production? These are just a few of the many factors designers must weigh when selecting materials for a product.

In this section, we will explore how advances in material science have expanded the range of materials available to designers, the complexities of selecting the right material, and the ethical and environmental considerations that must be accounted for in the design process.

Advances in Material Science: Expanding Material Choices

Material science has experienced extraordinary advancements in recent decades, providing designers with a vast array of materials to choose from, including "smart" materials and enhanced versions of traditional materials. These innovations enable designers to create products that solve problems in novel ways or improve upon existing designs.

Smart Materials

Smart materials are a revolutionary class of materials that can change their properties in response to external stimuli like temperature, pressure, or light. For example:

• Shape Memory Alloys (SMAs):These metals can "remember" their original shape and return to it when heated. They are used in applications like medical stents and eyeglass frames.
• Photochromic Materials:These materials, such as those in transition lenses, darken when exposed to UV light and revert to transparency when UV exposure decreases.
• Piezoelectric Materials:These generate an electrical charge in response to mechanical stress and are used in sensors and actuators.

Enhanced Classic Materials

Traditional materials like metals, plastics, and textiles have also been enhanced through innovations such as:

• Alloying:Combining metals to improve properties like strength or corrosion resistance (e.g., stainless steel).
• Composite Materials:Combining two or more materials to create a product with superior properties, such as carbon fiber-reinforced plastics for lightweight yet strong structures.