Glass fiber insulation is a very good insulating material. The diameter of glass fiber monofilament ranges from a few microns to twenty meters, which is equivalent to 1/20-1/5 of a hair strand. There are hundreds or even thousands of monofilaments, which are commonly used as reinforcing materials in composite materials, electrical insulating materials and thermal insulation materials, circuit boards, etc., and are widely used in various fields of the national economy.
Introduction of fiberglass board
Glass fiber is a very good insulating material! Glass fiber is an inorganic non-metallic material with excellent properties. The components are silica, alumina, calcium oxide, boron oxide, magnesium oxide, sodium oxide, and the like. It is a process of melting, drawing, winding, weaving, etc. by using glass balls or waste glass as raw materials. Finally, various types of products are formed.
Characteristics of glass fiber
Glass fiber is more resistant to temperature than non-combustible, non-combustible, anti-corrosive, heat-insulating and sound-insulating (especially glass wool), high tensile strength and good electrical insulation (such as alkali-free glass fiber). However, it is brittle and has poor abrasion resistance. Glass fiber is mainly used as electrical insulation material, industrial filter material, anti-corrosion, moisture-proof, heat-insulating, sound-proof and shock-absorbing materials. It can also be used as a reinforcing material to make reinforced plastic or reinforced rubber, reinforced plaster and reinforced cement. The use of organic materials to cover glass fibers increases flexibility and is used to make packaging fabrics, window screens, wall coverings, coverings, protective clothing, and electrical and acoustic insulation materials.
The concept of glass is generally a hard and fragile object, and it is not suitable as a structural material. However, if it is drawn into a wire, its strength is greatly increased and it is soft, so that it can finally become an excellent structural material after being formulated with a resin. The glass fiber increases in strength as its diameter becomes smaller. As a reinforcing fiber, glass fiber has the following characteristics. These characteristics make the use of glass fiber much wider than other types of fiber, and the development speed is far ahead of its characteristics as listed below:
(1) High tensile strength and small elongation (3%).
(2) High modulus of elasticity and good rigidity.
(3) The amount of elongation in the elastic limit is large and the tensile strength is high, so the absorption impact energy is large.
(4) It is an inorganic fiber, which is incombustible and chemically resistant. (5) The water absorption is small.
(6) Scale stability and heat resistance are good.
(7) It has good processability and can be used as a product of different forms such as strands, bundles, felts and woven fabrics.
(8) Transparent and transparent to light.
(9) The development of a surface treatment agent excellent in adhesion to a resin is completed.
(10) The price is cheap.
Classification of fiberglass sheet
According to the shape and length, glass fiber can be divided into continuous fiber, fixed length fiber and glass wool. According to the glass component, it can be divided into alkali-free, chemical-resistant, high-alkali, medium-alkali, high-strength, high-elasticity modulus and alkali-resistant glass. Fiber, etc. Glass fiber is divided into different grades according to composition, nature and use. According to the standard level, E-class glass fiber is most commonly used, widely used in electrical insulation materials; S-class is special fiber, although the output is small, but it is very important, because of its super strength, mainly used for military defense, such as bulletproof box; Grade C is more chemically resistant than Class E and is used in battery separators and chemical filters; Class A is alkaline glass fibers for the production of reinforcing materials.
Glass fiber composition and properties
The glass used to produce glass fiber is different from the glass of other glass products. The glass components used in the internationally commercial fibers are silica, alumina, calcium oxide, boron oxide, magnesium oxide, sodium oxide, etc., depending on the alkali content of the glass, can be classified into alkali-free glass fibers (sodium oxide). 0% to 2%, belonging to aluminoborosilicate glass), medium alkali glass fiber (sodium oxide 8% to 12%, is a soda-calcium silicate glass containing or not containing boron) and high alkali glass fiber (oxidation) Sodium 13% or more, is a soda lime 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, has good electrical insulation and mechanical properties, is widely used in the production of glass fiber for electrical insulation, and is also widely used in the production of glass fiber for glass reinforced plastic. Its disadvantage is that it is easily contaminated by inorganic acid. Erosion, it is not suitable for use in acidic environments.
2, C-glass is also known as medium-alkali glass, which is characterized by chemical resistance, especially acid resistance is better than alkali-free glass, but the electrical properties are poor, the mechanical strength is lower than that of alkali-free glass fiber by 10% to 20%, usually in foreign countries. Alkali glass fiber contains a certain amount of boron trioxide, while China’s medium alkali glass fiber is completely free of boron. In foreign countries, medium-alkali glass fiber is only used to produce corrosion-resistant glass fiber products, such as glass fiber surface felts, and also used to strengthen asphalt roofing materials. However, in China, alkali glass fiber occupies more than half of glass fiber production. (60%), widely used in the reinforcement of FRP and the production of filter fabrics, dressing fabrics, etc., because it is more competitive than alkali-free glass fiber.
3, high-strength glass fiber is characterized by high strength, high modulus, its single fiber tensile strength is 2800MPa, 25% higher than the alkali-free glass fiber tensile strength, elastic modulus 86000MPa, than the strength of E-glass fiber high. The FRP products produced by them are mostly used in military, space, bulletproof armor and sports equipment. However, due to the high price, it can not be promoted in civilian use, and the world’s output is about several thousand tons.
4, AR glass fiber is also known as alkali-resistant glass fiber, mainly developed to enhance cement.
5, A glass, also known as high alkali glass, is a typical sodium silicate glass, due to poor water resistance, rarely used in the production of glass fiber.
6. E-CR glass is an improved boron-free alkali-free glass for the production of glass fiber with good acid and water resistance. Its water resistance is 7-8 times better than that of alkali-free glass fiber, and its acid resistance is also higher than that of alkali glass fiber. It has many advantages and is a new variety developed for underground pipelines and storage tanks.
7. D glass, also known as low dielectric glass, is used to produce low dielectric glass fibers with good dielectric strength.
In addition to the above glass fiber components, a new alkali-free glass fiber has appeared in recent years, which is completely free of boron, thereby reducing environmental pollution, but its electrical insulation properties and mechanical properties are similar to those of conventional E glass. There is also a double-glass glass fiber that has been used in the production of glass wool and is said to have potential for use as a FRP reinforcement. In addition, there is fluorine-free glass fiber, which is an improved alkali-free glass fiber developed for environmental protection.