201-- The surface is very bright with dark light, its manganese content is high, nickel content is low, corrosion resistance is not as good as 304.

202-- has good mechanical properties and corrosion resistance, its room temperature strength is higher than 304

301 -- Good ductility for molding products.It can also be hardened by machine speed.Good weldability.The wear resistance and fatigue strength are better than 304 stainless steel.

302 - Corrosion resistance is similar to 304, with better strength due to higher carbon content.303 -- By adding a small amount of sulfur and phosphorus to make it more processed.304 -- that is, 18/8 stainless steel.GB brand is 0CR18NI9.309 -- Better temperature resistance than 304.

316 -- The second most widely used steel after 304, used mainly in the food industry and in surgical equipment, is added with molybdenum to give it a special corrosion resistant structure.It is also used as "Marine steel" because of its better resistance to chloride corrosion than 304.SS316 is commonly used in nuclear fuel recovery plants.Class 18/10 stainless steels are usually qualified for this application.321 -- Similar properties except that the risk of weld corrosion of the material is reduced due to the addition of titanium.

400 Series -- Ferritic and Martensitic Stainless Steel 408 -- Good heat resistance, weak corrosion resistance, 11% Cr, 8% Ni.409 -- The cheapest model (UK and US), usually used as a car exhaust pipe, is of ferritic stainless steel (chrome steel).410 -- martensite (high strength chrome steel), good wear resistance, poor corrosion resistance.416 -- The addition of sulfur improves the processability of the material.

420 -- "tool grade" martensitic steel, similar to Brinell high chromium steel, the earliest stainless steels.It's also used for surgical cutlery, and it can be very shiny.

430 -- Ferritic stainless steel, decorative, e.g. for automotive accessories.Good formability, but poor temperature resistance and corrosion resistance.440 -- high strength cutting steel, slightly higher carbon content, after proper heat treatment can obtain a high yield strength, hardness up to 58HRC, among the hardest stainless steels.The most common example of an application is the "razor blade".There are three commonly used models: 440A, 440B, 440C, and 440F (easy to process).500 series - heat resistant chromium alloy steel.600 series - martensitic precipitated hardening stainless steel.630 -- The most commonly used precipitation hardened stainless steel model, also commonly known as 17-4;Cr, 17% and 4% N.