422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B


Stainless steel AISI 422, X20CrMoWV12-1, UNS S42200, ASTM A437 Grade B4B, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200 martensitic creep resistant stainless steel according to AMS 5655, ASTM A565, DOD-F-24669/F, GE B50A951, B50A125 , RBC PP422, Siemens PDS-10705BU, EN 10088-3:2014, EN 10302, ASME, 10705BU, MIL S 861

422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B - Introduction and Application

Stainless steel 422, X20CrMoWV12-1,  1.4935, SUH 616, UNS 42200, ASTM A437 Grade B4B martensitic creep resistant stainless steel additional heavy metal alloying elements giving it good strength and temper resistance at higher temperatures up to 1200oF, Chrome-nickel steel with an austenitic structure with carbides. Alloying additions of molybdenum, vanadium and tungsten increase the melting temperature.  Similar to the 410 stainless this grade has the ability to be heat treated to multiple different strength levels.  Because of the temper resistance this alloy is often used in the power generation market as steam and gas turbine components or various other high heat components, mainly turbine blades and fasteners. B50A125E is a popular Creep resistant steel which is hardened and tempered to give critical reliability in high temperature applications with a usual upper continuous operating temperature limit of 580℃., 422 Stainless, UNS S42200, B50A, AISI 616, AMS 5655, ASTM A 565 GRD 616, DOD F 24669/7, MIL S 861, B50A125, B50A951A1, BS 970 442S19, EN61



Melted process

  • AOD+ESR
  • EAF+LF+VD+ESR
  • BEF+ESR

422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B - Chemical composition WT %

GradeChemical composition WT %
CSiMnPSCrMoNiVWOther
X20CrMoWV12-1, 1.49350.17-0.240.1-0.50.3-0.8Max 0.025Max 0.01511.0-12.50.8-1.20.3-0.80.25-0.350.4-0.6-
SUH 6160.20-0.25Max 0.50.5-1.0Max 0.04Max 0.0311.0-13.00.75-1.250.5-1.00.2-0.30.75-1.25Cu: 0.3
ASTM AISI 422, AISI 616, S422000.20-0.25Max 0.75Max 1.0Max 0.04Max 0.0311.0-12.50.75-1.250.5-1.00.15-0.300.75-1.25Cu: 0.5
B50A951 A10.20-0.250.2-0.50.5-1.00.0250.01511.0-12.50.9-1.250.5-1.00.2-0.30.9-1.25Tin:0.02, Al:0.025, Cu:0.15, Ti:0.25
B50A951 A2, A3, A40.20-0.250.2-0.50.5-1.00.0200.01511.0-12.50.9-1.250.5-1.00.2-0.30.9-1.25Tin:0.02, Al:0.025, Cu:0.15, Ti:0.25
B50A125










10705BU
0.18-0.27
0.550.47-1.030.0300.03011-12.50
0.9-1.250.5-1.0
0.2-0.30.9-1.25
BS 970










ASME B4B / ASTM A437 Grade B4B0.230.350.700.0190.001
11.400.975
0.7400.255
1.01
Sn:0.005, Al:0.025, Cu:0.075, Ti:0.01

Mechanical Property of 422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B

PropertiesMetricImperial
Elastic modulus190-210 GPa27557–30458 ksi
Poisson's ratio0.27-0.300.27-0.30

Mechanical properties of Q+T 700 Forgings of 1.4935, X20CrMoWV12-1, 422, SUH 616, UNS 42200

  • Ambient temperature: 
    • Re: > 500 MPa
    • Rm: 700-850 MPa
    • A: 15 %
  • Yield strength Re in high temperature: 
    • Testing temperature: 50 °C - > 465 MPa
    • Testing temperature: 100 °C - > 460 MPa
    • Testing temperature: 150 °C - > 445 MPa
    • Testing temperature: 200 °C - > 430 MPa
    • Testing temperature: 250 °C - > 415 MPa
    • Testing temperature: 300 °C - > 390 MPa
    • Testing temperature: 350 °C - > 380 MPa
    • Testing temperature: 400 °C - > 360 MPa
    • Testing temperature: 450 °C - > 330 MPa
    • Testing temperature: 500 °C - > 290 MPa
    • Testing temperature: 550 °C - > 250 MPa

Mechanical properties of Q+T 800 Forgings of 1.4935, X20CrMoWV12-1, 422, SUH 616, UNS 42200

  • Ambient temperature: 
    • Re: > 600 MPa
    • Rm: 800-950 MPa
    • A: 14 %Yield strength Re in high temperature: 
    • Testing temperature: 50 °C - > 585 MPa
    • Testing temperature: 100 °C - > 560 MPa
    • Testing temperature: 150 °C - > 545 MPa
    • Testing temperature: 200 °C - > 530 MPa
    • Testing temperature: 250 °C - > 505 MPa
    • Testing temperature: 300 °C - > 480 MPa
    • Testing temperature: 350 °C - > 450 MPa
    • Testing temperature: 400 °C - > 420 MPa
    • Testing temperature: 450 °C - > 380 MPa
    • Testing temperature: 500 °C - > 335 MPa
    • Testing temperature: 550 °C - > 280 MPa

Physical Property of 422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B

PropertiesMetricImperial
Density7.8 g/cm30.2817 lb/in³
  • Linear expansion coefficient: 10.5-12.5 *10-6m/(m*K)
  • Thermal conductivity: 24 W/(m*K)
  • Specific heat capacity: 460 J/(kg*K)
  • Young's modulus: 216 GPa
  • Electrical resistivity: 0.6 µΩ*m
  • Tensile strength Rm: > 600 MPa
  • Creep limit for max elongation 0.2% Rp0.2: > 800 MPa
  • Creep-rupture strength Ru: > 275 MPa; 500 °C; 100000 h

Creep limit for max elongation 0.2% Rp0.2 - high temperature test:

  • Testing temperature: 400 °C - > 420 MPa
  • Testing temperature: 500 °C - > 335 MPa

Heat Treatment of 422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B

  • Quenching: 1020-1070 °C 
  • Tempering: 680-780 °C

B50A125E temperatures of up to 1200ºF (649ºC).


Welding of 422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B

The steel is hard to weld. It is assigned to welding group 7.2 according to ISO/TR 20172.


Equivalent grades of 422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B

422, ASME B4B, 1.4935, X22CrMoWV12-1, SUH616, 20VNiWMoCr120, AISI 422, AISI 616, S42200, EW 4935, T502, 56B.I.; DE 4935, HWMoV3, SUH 616, B50A125, B50A951, 10705BU, AISI HNV-8, GOST 15Ch12WNMF, DIN X23CrMoWMnNiV12-1-1

422 Stainless steel, X20CrMoWV12-1, 1.4935, SUH 616, UNS 42200, B4B Martensitic & Precipitation hardened stainless steel stock list

Grade Shape Dimensionmm Qty.kg
616 Round bar Φ55mm 1180
616 ESR ingot 35000
Stainless Steel 422 Forgings 128x398x1100 2311
Stainless Steel 422 Forgings 128x398x1260 12344