Cold Rolled 316 321 Stainless Steel Round Bar 2mm 3mm 6mm Metal Rod

It can be divided into Cr system (SUS400), Cr-Ni system (SUS300), Cr-Mn-Ni system (SUS200) and precipitate hardening system (SUS600).
200 series - Chrome-nickel-manganese austenitic stainless steel
300 series - Chrome-nickel austenitic stainless steel
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 with 304, due to relatively high carbon and therefore better strength.
303 - It is trimmed by adding a small amount of sulfur and phosphorus.
304 -- 18/8 stainless steel. GB brand is 06Cr19Ni10.
309 - better temperature resistance than 304.
The second most widely used steel, after 304, is used in the food industry and surgical equipment, where molybdenum is added to give it a special structure that is resistant to corrosion. It is also used as "Marine steel" because of its better resistance to chloride corrosion than 304. SS316 is usually used in nuclear fuel reprocessing units. Grade 18/10 stainless steel is also usually qualified for this application class. [1]
Model 321 -- Similar to 304 except that titanium is added to reduce the risk of weld corrosion.
400 series -- ferrite and martensitic stainless steel
408 -- Heat resistance, mild corrosion resistance, 11% Cr, 8% Ni.
409 -- cheapest model (Anglo-American), usually used as automobile exhaust pipe, ferritic stainless steel (chrome).
410 -- Martensite (high strength chromium steel), good wear resistance, poor corrosion resistance.
416 -- Sulfur was added to improve the machinability of the material.
420 -- "blade grade" martensitic steel, similar to brinell high chromium steel, the earliest stainless steel. Also used for surgical knives, which can be made very bright.
430 -- Ferritic stainless steel, for decorative purposes, e.g. automotive accessories. Good formability, but poor temperature and corrosion resistance.
440 -- high strength cutting steel, slightly high in carbon, with appropriate heat treatment to achieve a high yield strength, hardness up to 58HRC, is among the hardest stainless steels. The most common example is the "razor blade". There are three common models: 440A, 440B, 440C, and 440F (easy to process).
Series 500 - Heat resistant chromium alloy steel.
600 series - Martensite precipitation hardened stainless steel.
630 -- The most commonly used precipitation hardened stainless steel model, also commonly called 17-4; 4% 17% Cr, Ni.