The chromium content is 18%, or so 8% nickel and elements of Molybdenum, Titanium, Nitrogen. Combination property is pretty well, can be corrosive for multiple
mediums. Those steels possess excellent plasticity, toughness, weldability, corrosion resistance and Non-magnetism or weak magnetism. and good corrosion resistance in the medium of oxidability and reducibility, which are for
processing the acid-resistant equipments, such as
anti-corrosive vessel,equipment lining, running piping, equipment parts
of nitric acid resistance, and also for main material of
stainless steel horologe accessories. Austenitic stainless steel
adopts solution treatment generally, that's to say, heating the steel to 1050~1150℃, then water cooling or wind cooling, to obtain single
phase austenite structure. Main steel grades are listed: ASTM XM-7, ASTM 310HCb, UNS S31603, ASTM 316LN, UNS S31653, ASTM XM-15, UNS S38100, ASTM F46, UNS S30600, ASTM XM-21, UNS S30452, AISI 317LN, UNS S31753, AISI/ASTM 316Ti, UNS S31635, ASTM 316LN, UNS S31653, ASTM 310MoLN, UNS S31050, UNS S38815.
Duplex stainless steel
Duplex (ferritic-austenitic) stainless steels maintain properties both ferritic steel and austenitic steel
and possess the feature of superplasticity, which have each half
austenitic and ferritic structures. Under the circumstances of
lower carbon content, chromium content 18% ~ 28%, Nickel content
3%~10%. Some other steels contain the alloy elements - Mo, Cu, Si, Nb, Ti, N and so on.Those steels possess the
properties of austenite and ferrite steels. Compared with
ferritic steels, duplex stainless steels have good plasticity and toughness, non-room temperature fragility, intergranular corrosion resistance and weldability, and alsomaintain the
features of ferritic stainless steel 475℃ frangibility, a higher heat conductivity coefficient, superplasticity.Compared with austenitic stainless steel, duplex stainless
steel possess high strength, intergranular corrosion resistance and
excellent chloride stress corrosion resistant. and
also superior pitting resistance. they take as a stainless steel of nickel saving. Main steel
grades are below listed: UNS S32205, ASTM 2305, UNS S32304, UNS S32900, UNS S31803, UNS S31200, AISI/ASTM 329, ASTM F55, UNS S32760.
Martensitic stainless steel
High strength, lower plasticity and weldability. Based on higher carbon content, martensitic steels possess
higher strength,hardness, abrasive resistance, but its corrosion
resistance is not so good, those steels are for mechanical
parts with higher mechanical property and normal corrosion
resistance. Such as mechanical spring, blades of steam turbines, hydraulic press valves. Those steels are used after quenching and tempering and annealing after forging, impacting as well. Main steel grades are below listed:ASTM XM-30, AISI/ASTM 440C, UNS S44004, ASTM 431, UNS S43100, AISI 410Cb, UNS S41040,
Precipitation hardening-stainless steel
Primary structures are austenite or martensite. The popular steel
grades of Precipitation hardening-stainlesssteel are 04Cr13Ni8Mo2Al, Crl7Ni4Cu4Nb, 0Crl7Ni7A1, 0Crl5Ni7Mo2A1, SUS 632, ASTM 632, UNS S15700, ASTM 634, ASTM XM-13, UNS S13800, UNS S35500, ASTM XM-25, UNS S45000, X8CrNiMoAll5-7-2, SUS 631, ASTM 631, UNS S17700, X7CrNiAll7-7, UNS S13800, ASTM 630, S17400. SUS630, STS630, X5CrNiCuNb16-4, which are normally through precipitation hardening (also
known as age-hardening) treatment.