First, chemical composition requirements
The chemical composition of stainless steel requirements are relatively strict, generally requiring chromium content of no less than 10.5%, while also adding other elements, such as nickel, molybdenum, titanium, etc., to improve its performance and corrosion resistance. In addition, stainless steel also requires a low iron content, usually requiring an iron content of no more than 0.08%.
Second, mechanical performance requirements
The mechanical properties of stainless steel mainly include strength, elongation and hardness. Strength refers to the ability to resist tensile and compressive forces, elongation refers to the ratio of the shape variable to the original length when the metal material deforms under the force, and hardness refers to the resistance generated when the metal material is subjected to external forces. The mechanical properties of stainless steel are high, and common standards include GB/T 4338, GB/T 1220 and so on.
Third, processing performance requirements
The machinability of stainless steel mainly includes machinability, weldability and plasticity. The machinability of stainless steel is generally poor, because the hardness of stainless steel is high, and stainless steel will also produce a large cutting heat, which is easy to lead to tool wear. The weldability of stainless steel is better, but welding personnel are required to master welding technology and appropriate welding materials. Stainless steel has good plasticity and is easy to process into various sizes and shapes.
4. Surface quality requirements
Stainless steel surface quality requirements are high, usually require no appearance defects, oxidation and removal of various impurities. The surface of stainless steel also requires a certain gloss and smoothness.
In short, stainless steel materials have high chemical composition requirements, mechanical performance requirements, processing performance requirements and surface quality requirements, which determine that stainless steel has excellent rust prevention, oxidation resistance, corrosion resistance and other characteristics. For the manufacturing industry, the selection of appropriate stainless steel materials has a very important impact on the quality and performance of the product.