Brass, also known as copper-zinc alloy. Containing 63%~65% copper and 35%~37% zinc, it is yellow. Its advantage is that it is easy to cut and process, but its disadvantage is that it is easy to change color. Commonly used in low-end spectacle frames and nose pad cores.
Copper-nickel-zinc-tin alloy is an alloy composed of 62% copper, 23% nickel, 13% zinc, and 2% tin. It has good elasticity and is often used on the bridge of the nose and temples of eyeglass frames after electroplating treatment.
Bronze generally refers to copper-tin alloy and contains a small amount of zinc and phosphorus. Since bronze contains a certain amount of tin element, it is more expensive. Its disadvantages are that it is difficult to process and has poor corrosion resistance to acids. However, it has good elasticity, antimagnetism, and wear resistance. It can be used in atmosphere, seawater, and steam. Its resistance to human body corrosion is superior to copper and brass, so it is suitable for use as spring and lens ring materials for spectacle frames.
Monel alloy is a type of 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 not containing chromium. Due to its high nickel content, it has the advantages of good strength, elasticity, corrosion resistance and strong welding, so it is often used to make mid-range eyeglass frames.
High nickel alloy, also known as nickel alloy. The specific gravity is 8.67, containing 84% nickel, 12.5% chromium, 5% silver, 1% copper and other elements. It is a high-grade nickel-chromium alloy material, which is more elastic and corrosion-resistant than Monel alloy. Some imported spectacle frames and domestic high-end frames mostly use this material.
Stainless steel is a type of nickel-chromium alloy. It mainly contains iron accounting for more than 70%, chromium 18%, nickel 8%, and other elements accounting for 0.1%~0.3%. It has good elasticity and corrosion resistance and is mostly used as temple material. Stainless steel materials containing 1% to 1.5% lead are mostly used as base materials for making screws or gold-plated frames. Its disadvantages are high strength and difficult welding processing.
Titanium, pure titanium is a silver-white metal. The specific gravity is 4.5, its biggest feature is light weight, and it has high strength, corrosion resistance and good plasticity. It is mostly used in the aerospace industry and is called "space metal". It was used to make eyeglass frames in the early 1980s, and processing problems such as cutting, polishing, welding and electroplating have gradually been solved, making titanium eyeglass frames basically popular. Products are mainly sourced from Japan. Titanium eyeglass frames are generally represented by the symbol Ti-P or TiTAN. This mark indicates that except for the nose bridge bracket, hinges and screws, other parts are made of titanium. The Ti-C symbol indicates that part of the eyeglass frame is made of titanium.
Gold and its alloys. Pure gold is golden yellow with a specific gravity of 19.3. It is one of the heaviest metals and will not be corroded or oxidized in the atmosphere. Gold is softer than silver and has good rolling properties. Therefore, pure gold is generally not used as the material for eyeglass frames, but alloys of gold, silver, copper, etc. are used. The gold content of the alloy is generally represented by "K". 24K is 100% pure gold. Glass frame materials are mostly made of K18, K14 and K12 alloys. The pure gold contents are: K18: 18/24×100=75%
It has certain characteristics of corrosion resistance, heat resistance, high strength and good elasticity. After strengthening and processing synthetic resin, it is used as spectacle frame material. It is also a thermoplastic resin.
C.Natural materials
Tortoiseshell, horn, precious wood, tortoiseshell is now a protected animal, so it is not allowed to make glasses. There are still glasses with horns and wood.
Plastic glasses material classification: PC/AC/nylon injection molded material glasses frames, acetate fiber glasses frames (the kind with copper pins inside the temples). TR90 PEI nylon ps wood plastic foam material.