How Frames Are Produced: Metal
Typically, metal frames are made form wire of varying gauges in a range of materials. The wire is either left rounded or flattened to the thickness required for the individual style.
Nickel Silver: Low-end metal framed sunglasses and readers employ a combination of nickel, copper and other alloys are made into wire and then pressed and tempered before being electroplated to varying colors and treatments. These frames, unless properly treated with anti-tarnish coatings, tend to turn color over time.
Monel: Made by combining nickel, copper, iron, manganese and trace amounts of other alloys, the Monel frame has the strength of steel with the weight of plastic and is corrosion resistant as well. Monel is used in the production of Jet engines to give strength with the flexibility necessary to handle the turbulence experienced in flight. This is a better quality process by which frames are made of specific alloys that allow them to keep their shape better than cheap metal frames. There is a precess for the production of the frame that has a high degree of tensile strength and resistance to permanent bends, utilizing an age-hardenable nickel-bronze alloy which is capable of being strengthened by a heat-aging treatment. The tendency for the frame to lose shape with the application of stress to the frame is, therefore, substantially reduced as compared to a similar frame that is not subjected to a heat-aging treatment step or frames made of alloys which cannot be strengthened by a heat-aging treatment.
Stainless Steel: A lightweight durable frame material that is used in higher end products. Composed of iron carbon and at least 10.5% chromium, these frames are typically constructed of thin wire and are flexible for adjustments. They are rust and corrosion resistant.
Aluminum – Magnesium Alloys: Marrying these two materials together when in a molten state and then pouring the alloy into stainless steel molds creates an incredible combination of a frame that is durable, corrosion free and lightweight and that feels cool on the face.
Titanium: The most expensive material for frame production. It is as strong as steel but 45% lighter. In fact it is said to have the highest strength to weight ratio of any material. Many companies claim to use 100% titanium when in reality they are using a titanium blend. It is hypoallergenic, non-corrosive, and one-third stronger than steel, making it an extremely desirable material for manufacturing frames. It’s also difficult and expensive to extract and refine and requires exacting manufacturing processes, all of which add to the cost. The colors applied to titanium frames can be quite elaborate and are typically in a matte finish. Though it is resistant to damage from sea water and chlorine titanium, is not typically used in water sport applications because of its high cost.