Inorganic adhesive is a new type of adhesive. It can withstand high temperature and low temperature, has low cost, is not easy to age, simple structure, and high adhesion.
The high temperature that ordinary organic adhesives can withstand is usually below 100°C. For example, latex is below 60°C, epoxy resin is around 100°C, and phenolic resin is around 220°C. Inorganic adhesives can withstand high temperatures up to 600-900°C, [1] After improving the composition, it can reach above 1800°C.
Someone once immersed objects bonded with inorganic adhesives in liquid oxygen at -186°C, but the bonding effect did not change. There is a kind of phosphoric acid copper monoxide inorganic glue, the main components are aluminum phosphate solution and copper monoxide powder. After this glue is applied, the surface will become very rough, in a staggered state, which will make the tensile strength of the article 3-5 times higher than that of the flat article. Inorganic adhesives are used for the bonding of rocket and spacecraft parts, the bonding of low-temperature surgical instruments, the bonding of automobile and ship engines, and the bonding and repair of oxygen generator parts.
Inorganic adhesives have the following characteristics:
1) High temperature resistance and low temperature resistance. The inorganic adhesive itself can withstand temperatures of about 1000°C or higher, and the improved inorganic adhesive can withstand high temperatures [1] 1800°C.
2) It is usually water-soluble, has low toxicity, does not burn, and has no environmental pollution.
3) The coefficient of thermal expansion is small, only 1/10 of steel and 1/3 of ceramics.
4) Oil resistance, radiation resistance, no aging, and good durability. However, it is not resistant to acid and alkali corrosion, poor water resistance, brittleness, and impact resistance.
5) It can be cured at room temperature, basically does not shrink, and some expand slightly. [2]
6) Socket connection and slot connection have high adhesive strength, so flat connection is not suitable. The sleeve tensile shear strength is greater than 100MPa.
7) Inorganic glue is mostly a kind of paste formed by mixing solid and liquid. The raw materials are easily available, the price is low, and the use is convenient.
