a month ago
- Kitchen aluminum foil is remarkably thin (10 μm) with a high aspect ratio, making it suitable for forming metamaterials and having properties like being impermeable to oxygen and water when thick enough (25 μm or more).
- It is highly reflective, conductive, corrosion-resistant, non-toxic, lightweight, and cheap (under 50¢/m²). Robert Lang's 'tissue foil' laminates tissue paper with foil for origami.
- Aluminum foil is made from alloys like 1100 and 1200, with room-temperature yield strengths of 30–170 MPa, remaining ductile down to absolute zero and melting at almost 650°C, suitable for cryogenic and high-temperature applications.
- When oxidized, it forms amorphous sapphire, which can be used as an insulator or abrasive, and aluminum foil can be used in fuel cells due to its high energy density.