takes you to understand the properties of FRP materials that are widely used today: glass is high in hardness but fragile, has good transparency, high temperature resistance, corrosion resistance, etc.; at the same time, steel is hard and not fragile, and also has the characteristics of high temperature resistance. So people began to think that if they could make a kind of glass that not only has the properties of glass hardness, high temperature resistance, and corrosion resistance, but also has the characteristics of being hard and unbreakable like steel, then this material will be of great use.
After research and experimentation, people finally produced such a composite material. It is a FRP material that can stand shoulder to shoulder with steel.
Let’s take a look at an experiment first to understand its performance. In a tree-lined valley surrounded by mountains, an experiment is underway. The people behind the bunker two hundred meters away were all staring at an oxygen cylinder in the middle of the valley. The air compressor rotates rhythmically, continuously inflating the oxygen cylinder through the alloy steel pipe. The pointer on the pressure gauge affects everyone's heart. The reading gradually increased from 100-200-400-500, until 700 kilograms and 1 square centimeter, only a loud noise was heard and the oxygen cylinder exploded! The people around jumped up cheering
Oxygen cylinder is a high-pressure container. The working pressure it bears is 150 kg/cm². In order to be safe to use, it is required to withstand three times the working pressure, which is 450 kg/cm². It is qualified if it does not burst. The oxygen cylinder tested above far exceeds the design requirements. What kind of steel is this made of? It is made of glass steel material, more precisely, it is made of glass steel material and plastic composite.
Glass is a hard and brittle material, and it shatters as soon as it is dropped. Can this FRP material with the name of glass withstand a drop? So a new experiment was carried out.
Inflate another glass fiber reinforced plastic oxygen cylinder to 150 kg/cm², and then roll down the valley from the top of the mountain. It collided with the rugged rocks and rolled to the bottom of the valley without bursting. The glass fiber reinforced plastic oxygen cylinder has passed the quality appraisal examination.
The tensile strength of ordinary glass is only one-eighth of ordinary steel. Melt the glass and pull it into a glass fiber that is only one tenth of the diameter of a hair. The original hard and fragile glass becomes a soft and tensile glass fiber, and its tensile strength can be increased by more than ten. Times.
Everyone knows that cement blocks are compressive and steel is tensile. Using steel as the bones and cement sand and gravel as the muscles, let them become one body, complement each other and become strong-this is reinforced concrete.
Similarly, if we use glass fiber as bones and synthetic resins (phenolic plastic, epoxy resin and polyester resin) as muscles, let them condense into one body, the material made has a tensile strength comparable to steel-- -Hence the name FRP material.