What are the characteristics of the stainless steel water pump material?
Stainless steel water pumps are widely used in the chemical industry because of their special properties of anti-corrosion and high temperature resistance. They are also used in the food processing industry because of their hygienic characteristics. However, you should pay attention to the quality of materials when purchasing, and focus on distinguishing between stainless steel and stainless steel. Although stainless iron can meet hygienic standards, it is not resistant to corrosion.
1, strong toughness
As we all know, the presence of bai stainless steel material and du body iron leads to the high hardness of the zhi material, especially under high temperature dao conditions, its actual high hardness and high strength make it difficult to achieve precise cutting during the machining process, and even more difficult Realize processing effects such as bending and curling.
2, high plasticity
During the processing of stainless steel, it exhibits greater plasticity, making the surface of the material attached to the chips produced during the processing difficult to be removed. That is to say, as the processing progresses, the plasticity it exhibits makes the material have a certain adhesion ability, causing processing difficulties.
3, high expansion coefficient
In the processing of stainless steel materials, as the processing work progresses, the material temperature also rises. At the same time, its poor heat dissipation capacity also results in easy deformation of the processed materials, which affects accuracy. In addition, the high temperature of the material also makes the temperature of the processing tool continue to be high, which accelerates its wear.
Why is stainless steel corrosion resistant?
All metals react with oxygen in the atmosphere to form an oxide film on the surface. Unfortunately, the iron oxide formed on ordinary carbon steel continues to oxidize, causing the corrosion to continue to expand and eventually forming holes. You can use oil or oxidation-resistant metals (such as zinc, nickel and chromium) for electroplating to ensure the surface of carbon steel, but, as people know, this protection is only a thin film. If the protective layer is damaged, the steel below will begin to rust.
The corrosion resistance of stainless steel depends on chromium, but because chromium is one of the components of steel, the protection methods are different. When the addition amount of chromium reaches 11.7% or more, the atmospheric corrosion resistance of steel is significantly increased, but the chromium content is more When it is high, although the corrosion resistance can still be improved, it is not obvious. The reason is that when chromium is used to alloy steel, the type of surface oxide is changed to a surface oxide similar to that formed on pure chromium metal. This tightly adhered chromium-rich oxide protects the surface and prevents further oxidation. This oxide layer is extremely thin, and the natural luster of the steel surface can be seen through it, giving the stainless steel a unique surface. And if the surface layer is damaged, the exposed steel surface will react with the atmosphere to repair itself, re-form this oxide "passivation film", and continue to play a protective role. Therefore, all stainless steel elements have a common characteristic, that is, the chromium content is above 105%.
The American Iron and Steel Institute uses three digits to indicate various standard grades of forgeable stainless steel. among them
1. Austenitic stainless steels are marked with 200 and 300 series numbers. For example, some common austenitic stainless steels are marked with 201, 304, 316 and 310
2, ferritic and martensitic stainless steels are represented by 400 series numbers.
3, ferritic stainless steel is marked with 430 and 446, martensitic stainless steel is marked with 410, 420 and 440C, duplex (austenite-ferrite)
Stainless steel, precipitation hardening stainless steel and high alloys with iron content less than 50% are usually named by patent names or trademarks
