Types and advantages of stainless steel

There are several types of stainless steel and what are the advantages?

1. According to the organizational structure at room temperature, there are martensitic, austenitic, ferritic and duplex stainless steels; according to the main chemical components, they can be basically divided into two major systems: chromium stainless steel and chromium-nickel stainless steel;

2. According to the use, there are nitric acid-resistant stainless steel, sulfuric acid-resistant stainless steel, seawater-resistant stainless steel, etc., according to the type of corrosion resistance, it can be divided into pitting corrosion-resistant stainless steel, stress corrosion-resistant stainless steel, intergranular corrosion-resistant stainless steel, etc.;

3. According to the functional characteristics, it can be divided into non-magnetic stainless steel, free-cutting stainless steel, low-temperature stainless steel, high-strength stainless steel and so on. Because stainless steel has a series of characteristics such as excellent corrosion resistance, formability, compatibility and toughness in a wide temperature range. Therefore, it has been widely used in heavy industry, light industry, daily necessities industry and building decoration industries.

The difference:

First of all, the density and proportion are different, and secondly, the degree of rust resistance is different. Of course, the price is very different. Ordinary 304 stainless steel is an alloy. The 304 clad stainless steel is a composite material composed of two or three alloys, usually the surface is 304, with a layer of other materials in the middle, or three layers.

Insulation cups are generally stainless steel, which is very common and common, just like stainless steel tableware in the cafeteria. There are also many kinds of stainless steel. Those with a CR content of more than 13% can be said to be stainless steel. The stainless steel used in general tableware is similar, but the thickness is different. And the steel used to make tableware and water cups must be stainless steel. 304 steel is also a kind of stainless steel, which belongs to stainless steel and is not a separate kind of steel.

The main characteristics of stainless steel:

1. Weldability. Different product uses have different requirements for welding performance. A class of tableware generally does not require welding performance. Even some pot enterprises. However, most products require good welding performance of raw materials, such as second-class tableware, thermos cups, steel pipes, water heaters, water dispensers, etc.

2. Corrosion resistance. Most stainless steel products require good corrosion resistance, such as first and second class tableware, kitchen utensils, water heaters, water dispensers, etc. Some foreign merchants also do corrosion resistance tests on the products: heating the NACL aqueous solution to boiling, pouring out the solution after a period of time, washing and drying, and weighing the weight loss to determine the degree of corrosion.

3. Polishing performance. In today's society, stainless steel products are generally polished during production. Only a few products, such as water heaters and water dispenser liner, do not need polishing. Therefore, this requires that the polishing performance of the raw material is very good.

4. Heat resistance. Heat resistance means that stainless steel can still maintain its excellent physical and mechanical properties at high temperature. The influence of carbon: carbon is strongly formed and stable in austenitic stainless steel. As an element that determines austenite and expands the austenite region, the ability of carbon to form austenite is about 30 times that of nickel. Carbon is an interstitial element that significantly increases the strength of austenitic stainless steels through solid solution strengthening. Carbon can also improve the stress corrosion resistance of austenitic stainless steel in highly concentrated CL compounds.

5. Corrosion resistance. When the amount of chromium atoms in the steel is not less than 12.5%. The potential of the steel can be changed abruptly, from a negative potential to a positive potential. Prevent electrochemical corrosion.