Flexon is a titanium-based alloy. This unique and popular material, originated by the eyeglass manufacturer Marchon, also is called "memory metal." Frames made of Flexon come back into shape even after twisting or bending. Flexon frames are lightweight, hypoallergenic and corrosion-resistant.
Marchon company officials describe the frame as about 25 percent lighter in weight than standard metals, giving you a much lighter feel on your face.
Frames made from aluminum are lightweight and highly corrosion-resistant. Aluminum is used primarily by high-end eyewear designers because of the unique look it creates.
Aluminum is the world's most abundant and widely used nonferrous metal (metal other than iron or steel). Pure aluminum is actually soft and weak, but commercial aluminum with small amounts of silicon and iron is hard and strong.