408: Good heat resistance, weak corrosion resistance, 11% Cr, 8% Ni
409: The cheapest model (British and American), usually used as car exhaust pipe, is a ferritic stainless steel (chrome steel)
410: Martensite (high-strength chromium steel), good wear resistance, poor corrosion resistance. 416: The addition of sulfur improves the processing performance of the material.
420: “Cutting tool grade” martensitic steel, similar to the earliest stainless steel such as Brinell high chromium steel. It is also used for surgical knives, which can be very bright
430: Ferritic stainless steel, for decoration, such as car accessories. Good formability, but poor temperature resistance and corrosion resistance
440: High-strength cutting tool steel with slightly higher carbon content. After proper heat treatment, higher yield strength can be obtained. The hardness can reach 58HRC, which is among the hardest stainless steels. The most common application example is “razor blades”. There are three commonly used models: 440A, 440B, 440C, and 440F (easy processing type)
