Research and Application of Adhesives (2)

3.3 For military applications In the military sector, adhesives also have a wide range of applications.
3.3.1 Tank Tank Engine Repair housing cracks are common flaws. Due to defects in the internal metal structure, stress concentration, fatigue, and prominent external forces often cause cracks in different parts of the engine body shell. If this type of problem is solved by welding, there are disadvantages such as brittleness, deformation, and strength degradation of the material. At the same time, electric energy and equipment are also wasted. The use of special adhesive technology to deal with such cracks will achieve fast, good and provincial results.

3.3.2 military boats fitted military boats hull to reduce weight and improve the strength of the hull they use disposable bonded FRP (fiber or composite material). Therefore, in the manufacture of such boats, structural adhesives consisting of the same epoxy resin or unsaturated polyester as FRP are used in large quantities. In contemporary national defense technology, stealth submarines are one of the hallmarks of the modernization of naval equipment. An important method for stealthing a submarine is to lay an anechoic tile on the shell of the submarine. Silencer tiles are rubbers with sound-absorbing properties. In order to achieve a firm bond between the sound-absorbing tile and the hull steel plate, it depends on the adhesive.

3.3.3 light bomber mainly for military aircraft outer subsonic or transonic flight, fuselage, wing skins in the aluminum alloy sheet with a thickness of 1.5mm or less, some only 0.4 ~ 0.8mm thick, under which the corrugations Profile reinforcement. It is very difficult to rivet the skin so thin, but the adhesive structure can not only overcome the deformation caused by riveting thin skin, the overall strength loss caused by rivet nesting, reducing the tooling, shorten the assembly cycle, and increase the corrosion resistance of the structure. Sex, fatigue resistance and breakage safety. Modern high-performance military aircraft, the use of adhesives for the sealing of the wing integral fuel tank or fuselage integral fuel tank. The adhesive seal between the plexiglass and the polyester belt in the cockpit of the enemy aircraft requires a high-performance adhesive.

3.3.4 missile warhead missile warheads heat shield adhesive is loaded against adverse conditions, to the structure layer (a light metal alloy material, special carbon fiber composite material) together with an outer thermal protection layer (inorganic composite materials, special resin-based composite material ). The connection between the thermal protection layer and the warhead uses a temperature-resistant adhesive of about 2000°C.

3.3.5 Preparation of camouflage materials For Army ground weapons, the threat is mainly from 8 to 14 μm thermal imaging cameras. The main way to achieve infrared stealth is to develop infrared camouflage coatings with different emissivities, through different emissivities of the coatings. The target shape performs effective infrared image segmentation to achieve the goal of blending the target with the background. From the research content of infrared stealth coatings, high transparent adhesives are one of the technical approaches adopted. The use of resins in the infrared atmosphere window of 8 to 14 μm does not contain absorbing groups to achieve the low radiation specificity of the adhesive itself in the infrared window. Radar coating is a kind of main material that can absorb electromagnetic wave and reduce the target radar characteristic signal, making it difficult to be found and recognized. It consists of absorbents and adhesives that determine the physical and mechanical properties of the absorbent coating and its application properties.

3.4 Anti-Terrorist Counter-Terrorism The United States Sandia National Experimental Center has designed two super adhesives for the purpose of preserving nuclear warheads placed in warehouses. One is the use of a pressure gun to launch the adhesive. Once the air is hardened immediately, when it is sprayed on the human body, the person will be immediately solidified, so that it cannot move. After the other adhesive has been launched, it will be buried like an avalanche, making it invisible, unable to hear sounds, and unable to move, but it can breathe to save lives. If terrorists invade the warehouse and grab a nuclear warhead, the best choice for engineers is to use such super adhesives. It is foreseeable that such super adhesives will be of great use in future battlefields.

4 Adhesive Development Trend
1) Develop solvent-free adhesives. Many current adhesives contain a lot of very volatile solvents that not only endanger people's physical and mental health, but also destroy the ozone layer in the atmosphere. In recent years, the public and the government have attracted great attention. This naturally brings a new development trend to the adhesive industry, namely the development of solvent-free adhesives.
2) Development of nano-adhesives. Nano-adhesives are an important part of the materials sector. The development of nano-adhesives is likely to grab a commanding height in the “nano-economy” rush across the globe. Nano-adhesives will be a dazzling new technology star.
3) Develop multifunctional adhesives. When an adhesive has multiple functions at the same time, its application value tends to increase sharply, so the multifunctional adhesive is one of the development trends of the adhesive industry.
4) Develop military and defense adhesives. The development of adhesives for military and national defense is a need for future wars, terrorism prevention and anti-terrorism. Therefore, it must have considerable development.

5 Conclusion <br> save energy and protect the environment, it is an important research topic in today's world must be addressed. For energy conservation and environmental protection, various equipment must be lightweight, recyclable, high-strength, and streamlined. In order to improve the efficiency of equipment production, installation and maintenance, all possible means to integrate adjacent parts (such as: the parts under the hood of a car) into a whole. To achieve this goal, bonding or connection technology is bound to be used. Because bonding has a series of outstanding advantages such as non-destructive and high strength, it has been widely used. Inorganic Phosphate Adhesives are used in the machining of all kinds of cutters, cutters, grinders, whetstones, grinding rods, measuring probes, and measuring rods; petroleum instruments require evaporation of certain strength, high temperature resistance, and insulation. Adhesion to the head of the stick; satisfactory results have been achieved in many aspects such as the sealing of rectifier components, bottles and cans, and high-voltage electromagnetic tubes. Silicate adhesives are widely used for the bonding of metals, glass, ceramics, inorganic silicate materials, and the like. Organic adhesives are more closely related to people's production and life. They are widely used in various fields such as construction, packaging, textile, and footwear. It can be said that it is closely related to human production and life. In some situations, adhesives play an irreplaceable role. The use of high temperature adhesives is the most effective way to achieve a non-detachable connection of carbon materials. For example, when artificial satellites and manned spacecraft pass through a thick atmosphere, the surface temperature can reach 2300 to 2600°C due to high-speed air currents, and they must be protected by high-temperature ablative materials. The connection can only be made with high temperature adhesives. As adhesives have so many outstanding advantages, they are getting more and more people's attention. In the field of materials science, it has developed into an independent branch of research. Of course, adhesives still have problems that need to be solved in some aspects, such as the high cost of inorganic high-temperature adhesives and the contamination of traditional organic adhesives. It is believed that with the further development of the adhesive modification work, the adhesive will have a broader prospect.