Carbon fiber has the characteristics of light weight, high strength, high modulus, corrosion resistance, electrical conductivity, good shielding performance and high wave absorption, and is mainly used in military industry, aerospace and other high-tech fields. However, with the rapid development of economy, the excellent performance of carbon fiber has been widely used in civil fields.
The main application fields of short carbon fiber include:
1. Reinforced and modified plastics: nylon (PA), polypropylene (PP), polycarbonate (PC), phenolic aldehyde (PF), polytetrafluoroethylene (PTFE), polyimide (PI), etc.
2 Building field: carbon fiber reinforced cement, conductive coating and antistatic property;
3 Electric heating field: conductive paper, electric heating plate, conductive surface felt, needled felt, etc.
4 shielding materials: manufacturing shielding smoke, shielding curtain wall, etc.
5 thermal insulation materials: carbon fiber reinforced refractory blanks and bricks, carbon fiber reinforced ceramics, etc.
6 new energy field: electrodes of fuel cells, etc.
Extended information:
Physical properties
Carbon fiber has two characteristics: strong tensile strength of carbon material and soft processability of fiber. Its weight is very light, its specific gravity is lighter than aluminum, less than 1/4 of steel, and its specific strength is 2 times that of iron. Compared with metal materials such as titanium, steel and aluminum, carbon fiber has the characteristics of high strength, high modulus, low density and small linear expansion coefficient in physical properties, and can be called the king of new materials.
chemical properties
the chemical properties of carbon fiber are similar to those of carbon, and it has good corrosion resistance to common organic solvents, acids and alkalis, and it is insoluble and does not swell, and its corrosion resistance is outstanding, and there is no rust problem at all. However, it has poor impact resistance and is easy to be damaged. Carbon fiber also has the characteristics of oil resistance, radiation resistance, radiation resistance, absorption of toxic gases and neutron deceleration.
carbon fiber has many excellent properties, such as high axial strength and modulus, low density, high specific performance, no creep, ultra-high temperature resistance in non-oxidizing environment, good fatigue resistance, specific heat and conductivity between nonmetal and metal, small thermal expansion coefficient and anisotropy, good corrosion resistance and good X-ray permeability. Good electrical and thermal conductivity, good electromagnetic shielding, etc.
Compared with the traditional glass fiber, the Young's modulus of carbon fiber is more than three times. Compared with Kevlar fiber, its Young's modulus is about twice that of Kevlar fiber, and it is insoluble and swelling in organic solvents, acids and alkalis, with outstanding corrosion resistance.
In order to obtain high-quality carbon fiber, we need to pay attention to the technical points:
(1) The primary task of preparing high-performance carbon fiber is to realize high purification, high strengthening, densification and smooth surface of precursor. The carbon fiber system engineering needs to start with the polymerization monomer of precursor. The quality of precursor not only determines the properties of carbon fiber, but also restricts its production cost. High-quality PAN precursor is the primary prerequisite for manufacturing high-performance carbon fiber. ?
(2) Minimizing impurity defects is the fundamental measure to improve the tensile strength of carbon fiber, and it is also a hot topic for scientific and technological workers. In a sense, the process of improving strength is essentially the process of reducing and reducing defects.
Reference: Baidu Encyclopedia-Carbon Fiber