Classification Details Of Glass Fiber
According to shape and length, glass fiber can be divided into continuous fiber, fixed length fiber and glass wool; According to the composition of glass, it can be divided into alkali free, chemical resistant, high alkali, medium alkali, high strength, high elastic modulus and alkali resistant glass fiber. Glass fiber is divided into different grades according to its composition, properties and uses. According to the standard grade rules, Grade E glass fiber is the most commonly used and widely used in electrical insulation materials; Grade s is a special fiber. Although its output value is small, it is very important. Because of its super strength, it is mainly used for military defense, such as bulletproof boxes; Grade C is more chemical resistant than Grade E, and is used for battery isolation plate and chemical poison filter; Class A is alkaline glass fiber, which is used to produce reinforcement materials. The composition and function of glass fiber are modified. The glass for producing glass fiber is different from that of other glass products. The glass used for the commercialized fiber in the world consists of silicon dioxide, aluminum oxide, calcium oxide, boron oxide, magnesium oxide, sodium oxide, etc. according to the alkali content in the glass, it can be divided into alkali free glass fiber (sodium oxide 0% ~ 2%, belonging to aluminum borosilicate glass) Medium alkali glass fiber (sodium oxide 8% ~ 12%, belonging to sodium calcium silicate glass containing or without boron) and high alkali glass fiber (sodium oxide more than 13%, belonging to sodium calcium silicate glass).
1. E-glass, also known as alkali free glass, is a borosilicate glass. It is the most widely used glass component for glass fiber. It has good electrical insulation and mechanical function. It is widely used to produce glass fiber for electrical insulation, and many are used to produce glass fiber for glass fiber reinforced plastics. Its disadvantage is that it is easy to be corroded by inorganic acid, so it is not suitable for use in acid environment.
2. C-glass, also known as medium alkali glass, is characterized by better chemical resistance, especially acid resistance, than non alkali glass, but poor electrical function. Its mechanical strength is 10% ~ 20% lower than that of non alkali glass fiber. Generally, foreign medium alkali glass fiber contains a certain amount of boron trioxide, while China's medium alkali glass fiber does not contain boron at all. In foreign countries, medium alkali glass fiber is only used to produce corrosion-resistant glass fiber products, such as glass fiber surface felt, and also used to strengthen asphalt roofing materials. However, in China, medium alkali glass fiber accounts for more than half (60%) of the output value of glass fiber, and is widely used in the reinforcement of glass fiber reinforced plastics and the production of filter fabrics and binding fabrics. Because its price is lower than that of non alkali glass fiber, it has strong competitiveness.
3. High strength glass fiber is characterized by high strength and high modulus. Its single fiber tensile strength is 2800mpa, about 25% higher than that of alkali free glass fiber, and its elastic modulus is 86000mpa, higher than that of E-glass fiber. Their FRP products are mostly used in military industry, space, bulletproof armor and sports equipment. However, because of the high price, it can not be popularized in the civil area, and the world output value is about several thousand tons.
