The metal materials used in glasses frame are copper alloy, nickel alloy and precious metal. It is required to have certain hardness, softness, elasticity, wear resistance, corrosion resistance, light weight, luster and good color. Therefore, almost all metal materials used to make glasses frame are alloy or used after metal surface processing.

1. Zinc white copper, also known as foreign white or silver. The main components are copper, including 64% copper, 18% nickel and 18% zinc, and 8.8% of the total. It has a certain corrosion resistance and good elasticity, and low cost and easy to process. It is mainly used for hinge, pile head and nose beam support, and the low-end glasses are mostly made of zinc and copper. When used, it is rusted in copper green after being corroded by sweat.

2. Brass, also known as copper zinc alloy. The results showed that the content of copper was 63% - 65%, zinc was 35% - 37%, which was yellow. The advantage is that it is easy to cut

Processing, the disadvantage is easy to change color. It is commonly used in low-grade glasses frame and nose support core.

3. Copper nickel zinc tin alloy is composed of 62% copper, 23% nickel, 13% zinc and 2% tin. It has good elasticity, and is often used in the nose beam and leg of the spectacle frame after electroplating.

4. Bronze, generally copper tin alloy, and contains a small amount of zinc and phosphorus. Due to the amount of tin in bronze, the price is high, and its disadvantage is that it is difficult to process and has poor corrosion resistance to acids, but it has good elasticity, magnetism resistance and wear resistance. It is better than copper and brass in the air, sea water and steam, so it is suitable for the spring and ring materials of glasses frame.

5. Monel alloy, belonging to a nickel copper alloy. The specific gravity is 8.9, containing 63% - 67% nickel, 28% - 31% copper, and a small amount of iron and manganese. It is characterized by no chromium, because of its high nickel content, it has good strength, elasticity, corrosion resistance and strong welding, so it is often used to manufacture middle gear glasses frame.

6. High nickel alloy, also known as nickel alloy. The material is advanced nickel chromium alloy material, which has more elasticity and corrosion resistance compared with Monel alloy. Some imported glasses and domestic high-grade shelves are mostly made of this material.

7. Stainless steel, a nickel chromium alloy. The main iron content is more than 70%, chromium 18%, nickel 8%, other elements account for 0.1% - 0.3%. It is used in the material of mirror leg and stainless steel with 1% - 1.5% lead element is mainly used for the base material of screw or gold holder. The disadvantages are that the strength is large and the welding is difficult.

8. Titanium, pure titanium is a silver white metal. The specific gravity is 4.5, and the weight is the biggest feature, and it has high strength, corrosion resistance and good plasticity. It is widely used in the aerospace industry, and is called "space metal". It has been used to make glasses frame in early 1980s, which has gradually solved the processing problems of cutting, polishing, welding and electroplating, and made titanium glasses widely used. The products are mainly from Japan.

Titanium glasses frame generally means Ti-P or Titan, which indicates that except for the nose beam bracket, hinge and screw, other parts are made of titanium, and ti-c symbol indicates that part of the spectacle frame is made of titanium.

9. Gold and its alloy, pure gold is golden yellow, with a specific gravity of 19.3, which is one of the heaviest metals, and will not be corroded and oxidized in the atmosphere. Gold is softer than silver, and has good rolling property. Therefore, it is not necessary to use pure gold as the eyewear material, but the alloy of gold, silver and copper is used.

The gold content of the alloy is generally expressed by "K". 24K is 100% pure gold. The glasses are made of K18, K14 and K12 alloys. The content of pure gold is k18:18/24, respectively × 100=75% ； K14：14/24 × 100=58.3% ； K12：12/24 × 100 = 50% and so on.

10. Platinum, or gold alloy. The glasses frame materials are mainly K14 platinum, which consists of 58.3% pure gold, 17% nickel, 8.5% zinc and 16% copper.

11. Platinum and platinum group, pure platinum, as soft as gold and silver, is generally used as other platinum elements to form alloys. Platinum elements include platinum, palladium, iridium, osmium, rhodium and ruthenium, etc., and the above elements are collectively referred to as platinum group. The glasses are usually made of platinum iridium alloy, which has a large proportion. Rhodium and palladium are mostly used in the electroplating of metal glasses.

12. Baojin, also known as grinding, adding and rolling gold, is a layer of KJIN, about 10-50 thick, which is wrapped in the base metal μ m。 It has the property of gold and is characterized by low cost. Therefore, it is mostly used in high-grade mirror frame. The base materials of the metal clad are generally copper, brass, nickel and gold alloy, and the commonly used metal clad frames are K18, K14, K12 and K10.

There are two ways to express the gold-clad glasses frame. That is, when the weight ratio of gold content is more than 1/20, it is expressed by GF and RGP when the weight ratio is less than 1/20.

For example: ① 1 / 10 12K gf:1/10 means 1/10 of gold content × 12/24=1/20； 12K represents 12K alloy; GF represents the gold deposit symbol. ② 1 / 10 10K RGP: 1 / 10 means 1 / 10 of gold content × 10/24=1/24； 10K represents 10K alloy; RGP represents the gold deposit symbol for less than 1/20.

13. Aluminum alloy

Pure aluminum is soft, silver white, and is generally aluminum alloy. Aluminum alloy has light weight, good corrosion resistance, certain hardness, good cold forming characteristics, and the surface can be treated into thin and hard oxide layer, and can be dyed into various colors. At present, the gasket at the connection of the titanium frame mirror frame is made of aluminum alloy, and the whole glasses are made of aluminum alloy, which is rich in color.

14. Memory metal

Also known as memory titanium gold or NT alloy, it is a mixture of titanium and nickel after high temperature treatment. It has the advantages of light and super elasticity than the general titanium alloy.

Advantages and disadvantages of metal mirror frame

The copper frame in metal frame is cheap, but it is easy to rust and oxidize, and its flexibility is poor; But some alloy frames such as titanium alloy and nickel alloy are relatively good, corrosion resistant and not easy to rust, and belong to medium and high-grade products.

Corrosion resistance of pure titanium mirror frame

The corrosion resistance and plasticity of pure titanium frame are better, and a small amount of other elements can be added to make the corrosion resistance and elasticity better, which is the material for manufacturing high-grade mirror frame; There are also alloy frames of gold, such as 18K, 14K and 9K GOLD, which are relatively high-grade and also higher-grade platinum frames. It is not common in the market, but some are gold-plated frames, which makes the cost cheaper