In the process of ventilation inside and outside the tunnel, the flowing air pressure in the tunnel is first transmitted to the inside of the fan through the impeller of the fan, and then discharged through the exhaust outlet after being treated by the motor. In use, the impeller needs to face a complex environment and is also in direct contact with various objects. Therefore, the impeller is the key in the process of use and maintenance. Today, I'll show you the materials of the impeller.
The impeller is usually made of stainless steel, which is light in weight, has certain corrosion resistance and low in cost
1： Austenitic stainless steel
There are a lot of impurities in this kind of stainless steel, including titanium, manganese, nitrogen and chromium. Under normal temperature, it has good plasticity and flexibility, oxidation resistance and good comprehensive performance. Generally, medium and high-end fans use this kind of stainless steel as their fan impeller.
2： Ferritic stainless steel
The content of metal chromium in ferritic stainless steel can reach one-third and has certain corrosivity, but its mechanical properties are poor, it will deform in a small range under large impact force, it has certain anti-oxidation ability in high-temperature environment, and its coefficient of thermal expansion is small.
3： Martensitic stainless steel
Here, stainless steel has high hardness and strength, relatively poor plasticity and good mechanical properties. It will not be corroded in acidic environment. Moreover, it has stable physical properties at high and low temperatures. Generally, high-end tunnel fans in series use martensitic stainless steel as the material of their fan impellers.
