AISI 431 / S43100/ 1.4057 SS 431 STAINLESS STEEL BARS

440 Stainless Steel, Stainless Steel 440b Round Bar431 is a high chromium-low nickel high hardenability Martensitic stainless steel with high strength and good corrosion resistance, as generally supplied hardened and tempered in the tensile range 850 – 1000 Mpa (condition T) Brinell range 248 – 302. Characterised by very good corrosion resistance in general atmospheric corrosive environments, good resistance to mild marine and industrial atmospheres, resistant to many organic materials, nitric acid and petroleum products coupled with high tensile and high yield strength plus excellent toughness in the hardened and tempered condition.

431 due to its excellent hardenability is capable of being through hardened up to Rc44, depending upon carbon content and section size. Small sections can be air cooled and larger sections oil quenched for maximum through hardness. Pre hardened and tempered 431 will also respond readily to nitriding achieving a typical surface hardness of over Rc65. The nitriding process however reduces the corrosion resistance and is therefore not generally recommended except for critical applications where the benefit outweighs all other considerations. Used extensively for parts requiring a combination of high tensile strength, good toughness and good corrosion resistant properties.