titre page grades E

Grades correlations

Type Commercial AISI Digital NFA Symbolic UNS
Austenitic 304 304 1.4301 Z7 CN 18.09 X5CrNi18-10 S30400
Austenitic 304L 304L 1.4306 Z3 CN 18.10/
Z3 CN 19.11
X2CrNi19-11 S30403
Austenitic 321 321 1.4541 Z6 CNT 18.10 X6CrNiTi18-10 S32100
Austenitic 316 316 1.4401 Z7 CND 17.12.02 X5CrNiMo17-12-2 S31600
Austenitic 316L 316L 1.4404
Z 3 CND 17-12-02
X2CrNiMo17-12-2 S31603
Austenitic 316L (Mo+ ) 316L Mo sup 1.4435 Z3 CND 18.14.03   X2CrNiMo18-14-3 S31603
Austenitic 316Ti 316Ti 1.4571 Z6 CNDT 17.12 X6CrNiMoTi17-12-2        S31635
Austenitic 254 SMO   1.4547 X1CrNiMoCuN20-18-7  
Austenitic 317L 317L 1.4438 Z 3 CND 19-15-04 X 2 Cr Ni Mo N 18-15-4 S31703
Austenitic-ferritic Duplex / 318LN Duplex / 318LN 1.4462 Z3 CND 22.05.03   X2CrNiMoN22-5-3 S31803
Super Austenitic Uranus B6 904L 1.4539 Z1 NCDU 25.20.04  X1NiCrMoCu25-20-5      N08904
Super Austenitic Sanicro 28 928 1.4563 Z1 NCDU 31.27.03 X1NiCrMoCu31-27-7 N08028
Refractory 310S 310S 1.4845 Z8 CN 25.20          X8CrNi25-21 S31008
Nickel Nickel 200            Alloy 200 2.4066   Ni99-2 N02200
Nickel Nickel 201 Alloy 201 2.4068   LC-Ni99 N02201
Nickel and Alloys Monel 400 Alloy 400 2.4360   NiCu30Fe N04400
Nickel and Alloys Inconel 600 Alloy 600 2.4816 NC 15 Fe NiCr15Fe N06600
Nickel and Alloys Inconel 601 Alloy 601 2.4851   NiCr23Fe N06601
Nickel and Alloys Inconel 625 Alloy 625 2.4856 NC 220N b NiCr22Mo9Nb N06625
Nickel and Alloys Incoloy 800 Alloy 800 1.4876   X10NiCrAlTi33-20          N08800
Nickel and Alloys Incoloy 800 HT    Alloy 800 HT    1.4959   X8NiCrAlTi33-20 N08811
Nickel and Alloys Incoloy 825 Alloy 825 2.4858 NC 21FeDU NiCr21Mo N08825
Nickel and Alloys Hastelloy C22 Alloy C22 2.4602   NiCr21Mo14W N06022
Nickel and Alloys Hastelloy C276 Alloy C276 2.4819 NC 170 NiMo16Cr15W N10276
Titanium Titanium Gr2 Gr2 3.7035   Ti2 R60400

Stainless steels corrosion resistance

  • 304 => It has an austenitic stainless steel base. Excellent welding, also has good corrosion resistance at room temperature. If this type of steel is kept for some time in the critical temperature range between 450 ° and 850 ° C, there is a chance of chromium carbide intercrystalline precipitation and therefore intergranular corrosion.
  • 304L => This is a variant of 304 containing less than 0.03% C, which ensures a very low chromium carbide formation if kept long time in the critical temperature range and entails a very low risk of intergranular corrosion.
  • 321 => This type of steel includes the 304 elements to which titanium was added to prevent chromium carbide formation. Thus, there is no intergranular corrosion phenomenon and is particularly recommended in case of prolonged use in the critical temperature range. Resilient to scaling up to 800 ° C.
  • 316 => It contains an addition of 2-3% molybdenum which makes it particularly resistant to chemical agents that have a reducing effect. Within the critical temperature range, it also presents the risk of chromium carbide precipitation.
  • 316L => With a carbon content less than 0.03%, the chromium carbide formation is very low and has good resistance to intergranular corrosion.
  • 316Ti =>The addition of titanium prevents chromium carbide formation, making it a suitable material for prolonged use in the critical temperature range. It resists scaling up to temperatures exceeding 800 ° C.
  • 904L => Stainless steel 904L is designed for use under severe corrosion conditions mainly applied in offshore industries, oil refineries, chemical and petrochemical industries. It is characterised by the following properties:
    • very good resistance to attacks in acidic conditions, such as sulfuric, phosphoric and acetic acids.
    • very good resistance to pitting corrosion in neutral solutions containing chlorine. Higher resistance to interstitial corrosion than types 304 and 316L steels.
    • very good resistance to stress corrosion.
    • good weldability.
  • Alloy 800 (Inconel 800*) => refractory alloy with high levels of nickel and chromium. Resistant to scaling up to 1100 ° C, high breaking load and good resistance to high temperature corrosion .
  • Alloy 825 (Inconel 825) => nickel and chromium alloy resistant to high-temperature corrosion, in particular from sulfuric acid as well as intergranular corrosion .
  • Alloy 600 (Inconel 600*) => This is the best quality refractory alloy. Resistant to scaling up to 1200 ° C, has a high breaking load and excellent resistance to high temperature corrosion.
  • Alloy 400 (Monel 400*) => nickel-copper alloy resistant to corrosion by sea water, sulfuric, hydrochloric and phosphoric acids. It retains good mechanical strength and good toughness at temperatures up to 400 ° C.

* : Trademarks INCO-ALLOYS