1. Lightweight
The density of carbon fiber ranges from 1.5 to 2.0 g/cm 3, which is much smaller than most metal materials. Even lightweight aluminum is twice that of carbon fiber. The resin matrix of carbon fiber is mostly used, and the density of most resins is lower than that of carbon fiber filaments. Therefore, the weight of carbon fiber composite materials has an advantage over metal materials. Compared with our common steel materials, carbon fiber composite materials are more than four times lighter.
The application of carbon fiber composite materials in the manufacturing of military containers can greatly reduce their overall quality and play a very active role in long-distance, difficult-to-load and unload military transportation. But light weight is only one of the characteristics of carbon fiber composite materials, and plastic materials can achieve similar weight advantages. Another main feature of carbon fiber composites is their high strength and stiffness, which are often used as an upgraded substitute for metal materials in application fields.
2. High strength and high rigidity
The tensile strength of carbon fiber composite materials is generally above 3500Mpa, which is 7 to 9 times that of steel, and the tensile elastic modulus is 23000 to 43000Mpa, which is also higher than steel. Therefore, the specific strength of CFRP, that is, the ratio of material strength to its density, can reach more than 2000Mpa/(g/cm3), while the specific strength of A3 steel is only about 59Mpa/(g/cm3), and its specific modulus is also higher than steel .
3. Good corrosion resistance
Carbon fiber is a non-metallic material with low electrochemical activity, and its excellent properties such as elastic modulus and strength remain basically unchanged in certain acid and alkali salts. Therefore, carbon fiber, as a reinforcing material, has sufficient corrosion resistance. Carbon fiber military containers have a variety of corrosion-resistant properties. For example, in the natural environment, resistance to light and radiation is called weather resistance, and in some high-humidity environments, such as being exposed to rain, it can be called water resistance, and of course resistance to corrosion by chemical media.
4. Good electromagnetic shielding performance
The volume resistivity of carbon fiber is generally between (0.8-1.8)×10-3ω·cm, and the electrical conductivity increases with the increase of heat treatment temperature. Therefore, after graphitization at high temperature, carbon fiber can become an excellent reflective material for electromagnetic waves.
Carbon fiber surface modification can improve the electromagnetic shielding performance of carbon fiber. The methods mainly include surface activation, surface deposition, surface metallization and cross-section deformation. By activating the surface of continuous carbon fibers, multiple reflections of carbon fiber resin-based composites can be increased, thereby improving the shielding effectiveness of carbon fiber composites.
5. Good impact resistance and long service life
Carbon fiber, aluminum alloy, nylon PA11 and PP plastic transport box samples of the same size were placed in a standard atmospheric pressure environment, and impact tests were conducted with a pulse width of 11 milliseconds and an acceleration of 150 m/s2, three times in each of the three axes, and at the same Highly drop test. After impact vibration tests and drop tests, the carbon fiber and PP plastic boxes were well preserved and maintained their original strength in routine performance tests, while the aluminum alloy boxes were significantly deformed and the nylon PA11 boxes cracked, with the strength only about 50% of that before the test.