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Turbine Blade Steel

AISI 422, SUH 616, B50A951, 1.4935, X20CrMoWV12-1

December 29, 2022 | Tags: , , , , , , , , , ,
AISI 422, S42200, 616

AISI 422, Alloy 616, 1.4935, X20CrMoWV12-1 creep resistant martensitic stainless steels are high-alloy steels that exhibit better corrosion resistance than other steels, 12% Chromi um stainless steel used for thermal engine components in power plants, mainly turbine blades, Steam Turbine buckets, bolting fasteners, valves, and other miscellaneous components. Max temperature for continous operating is 580 °C.Chrome-nickel steel with an austenitic structure with carbides. Alloying additions of molybdenum, vanadium and tungsten increase the melting temperature, thus having a positive effect on creep resistance. acc.to B50A951 A1, A2, SIEMENS 10705BL/M, 10705BR, 10705BU. ASME SA-437 Grade B4B Alloy Steel Turbine-Type Bolting Material Specially Heat Treated for High-Temperature Service. ASTM A437 Grade B4B Stainless and Alloy-Steel Turbine-Type Bolting Specially Heat Treated for High-Temperature Service. ASTM A565 Grade 616 Martensitic Stainless Steel Bars for High-Temperature Service. JIS G4311 SUH 616 Heat-resisting steel bars and wire rods. SAE J 775 SUH 616 Engine poppet valve information report.


Melt Practice: EAF+AOD+IC+ESR

Table of contents

Chemical Composition

GradeChemical composition WT %
CSiMnPSCrMoNiVWCuSnAlCoTi
Ge Power B50A951 A10.20-0.250.20-0.500.50-1.00Max 0.025Max 0.01511.00-12.500.90-1.250.50-1.000.20-0.300.90-1.25Max 0.15Max 0.02Max 0.0250.200.025
Ge Power B50A951 A20.20-0.250.20-0.500.50-1.00Max 0.020Max 0.01011.00-12.500.90-1.250.50-1.000.20-0.300.90-1.25Max 0.15Max 0.02Max 0.0250.20-
Ge Power B50A249 S120.20-0.250.20-0.500.50-0.900.0250.02511-12.500.9-1.250.5-1.00.2-0.30.9-1.25
-0.02
0.0250.200.05
ASME B4B, ASTM Grade B4B0.20-0.250.20-0.500.50-1.00Max 0.025Max 0.02511.00-12.500.90-1.250.50-1.000.20-0.300.90-1.25-Max 0.04Max 0.05
Max 0.050
ASTM A565 6160.20-0.25Max 0.500.50-1.00Max 0.025Max 0.02511.00-12.500.90-1.250.50-1.000.20-0.300.90-1.25-----
EN 1.4935, X20CrMoWV12-10.17-0.240.10-0.500.30-0.80Max 0.025Max 0.01511.0-12.50.80-1.200.3-0.80.25-0.350.4-0.6-



JIS SUH 6160.20-0.25Max 0.500.50-1.00Max 0.040Max 0.0311.0-13.00.75-1.250.5-1.00.2-0.30.75-1.25Max 0.3



ASTM AISI 422, AISI 616, S422000.20-0.25Max 0.75Max 1.00Max 0.040Max 0.0311.0-12.50.75-1.250.5-1.00.15-0.300.75-1.25Max 0.5



Mechanical Properties

Type 422 Mechanical properties acc. to GE B50A951

  • Type 422 Class A1, A2, A4
    • Tensile strength KSI(MPa): Min 140(965)
    • Yield Strength 0.02%, Offset KSI(MPa): Min 90(620) *
    • Elong. In 2": Min 13 %
    • RA: Min 35%
    • Brinell Hardness, 3000Kg laod: 285-331
    • Kv, Min at  R.T.  ft-lb(J): 10(13.36)
  • Type 422 Class A3
    • Tensile strength KSI(MPa): Min 110(759)
    • Yield Strength 0.02%, Offset KSI(MPa): Min 80(555) *
    • Elong. In 2": Min 18 %
    • RA: Min 50%
    • Brinell Hardness, 3000Kg laod: 223-269
    • Kv, Min at  R.T.  ft-lb(J): 25(33.90)

Tensile Requirements (B50A249B Only)

  • Tensile Strength, psi, min. 140,000
  • Yield Strength, psi, 0.02%, min. 90,000
  • Elongation, % in 2 inches, min. 12
  • Reduction of Area, %, min. 25
  • Charpy V-Notch Impact Energy Requirements (B50A249B Only)

    • Two Charpy V-Notch Impact energy tests shall be conducted at room temperature (70F +/-10F) and have following properties:

    Standard Charpy V-Notch Impact, ft-lb, min. 10

  • Hardness Requirements

    • Two Brinell Hardness measurements shall be taken at the 0-degree and 180 Degree locations on one end and at the 90-degree and 270-degree locations on the opposite end of each forging. The measurements shall be taken at each end, on either the end face or a radial face in close proximity to the end. All measurements must meet the following requirements:

    Brinell Hardness Number, 3000 kg load 290-332

Stress Rupture Requirements (B50A249B Only)

Smooth bar stress rupture tests shall be conducted on each forging or each heat treated forging length. The test may be discontinued after the minimum requirement for time to rupture has been exceeded. The test must meet the following requirements:

  • Temperature (Degree F): 1200
  • Stress (psi): 26,000
  • Min. Time to Rupture (hrs.): 25

1.4935 Mechanical properties acc. to EN 10302

  • +QT700
    • Tensile strength KSI(MPa): 700 to 850
    • Yield Strength 0.02%, Offset KSI(MPa): Min 500
    • A5 15%
  • +QT800
    • Tensile strength KSI(MPa): 800 to 950
    • Yield Strength 0.02%, Offset KSI(MPa): Min 600
    • A5 14%

Grade B4B Stress Rupture

  • Test Method: ASTM E139
  • Temperature: 650 °C
  • Load:200 MPa
  • Result: Life = 25 hours,Elongation and Reduction of Area = For information On bar having lowest hardness for each heat lot.

1.4935 QT700 Creep

temperature,(℃)Time,(h)1% Rp1(MPa)0.5% Rp0.5(MPa)0.2% Rp0.2(MPa)0.1% Rp0.1(MPa)CRS(MPa)
47010000.0h324.0---368.0
470100000.0h260.0---309.0
470200000.0h----285.0
48010000.0h299.0---345.0
480100000.0h236.0---284.0
480200000.0h----262.0
49010000.0h269.0---319.0
490100000.0h213.0---260.0
490200000.0h----237.0
50010000.0h247.0---294.0
500100000.0h190.0---235.0
500200000.0h----215.0
51010000.0h227.0---274.0
510100000.0h169.0---211.0
510200000.0h----191.0
52010000.0h207.0---253.0
520100000.0h147.0---186.0
520200000.0h----167.0
53010000.0h187.0---232.0
530100000.0h130.0---167.0
530200000.0h----147.0
54010000.0h170.0---213.0
540100000.0h114.0---147.0
540200000.0h----128.0
55010000.0h151.0---192.0
550100000.0h98.0---128.0
550200000.0h----111.0
56010000.0h135.0---173.0
560100000.0h85.0---112.0
560200000.0h----96.0
57010000.0h118.0---154.0
570100000.0h72.0---96.0
570200000.0h----81.0
58010000.0h103.0---136.0
580100000.0h61.0---82.0
580200000.0h----68.0
59010000.0h90.0---119.0
590100000.0h52.0---70.0
590200000.0h----58.0
60010000.0h75.0---101.0
600100000.0h43.0---59.0
600200000.0h----48.0
61010000.0h64.0---87.0
610100000.0h36.0---50.0
610200000.0h----40.0
62010000.0h53.0---73.0
620100000.0h30.0---42.0
620200000.0h----33.0
63010000.0h44.0---60.0
630100000.0h25.0---34.0
630200000.0h----27.0
64010000.0h36.0---49.0
640100000.0h20.0---28.0
640200000.0h----22.0
65010000.0h29.0---40.0
650100000.0h17.0---23.0
650200000.0h----18.0

Physical Properties

Density: 7.7 g/cm3 

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: Min 800 MPa 

Creep-rupture strength Ru: Min 275 MPa; 500°C; 100000h

Heat Treatment

Austenitization-Material shall be heat treatedto1875-1925F and held at temperature for a sufficient time to assure uniform temperature within the load and each part thereof.

Quenching -Material shall be quenched to a temperature below 600℉ and then cooled to a temperature below theM(approximately 150℉) to assure complete transformation.

B50A951 A1-Material shall be oil quenched.Use of air quenching is prohibited.

B50A951 A2, A3, A4-Material shall be quenched in oil or rapidly moving air.

Tempering-Material shall be uniformly heated to the tempering temperature of 1150F° minimum.

Heat treatment for 1.4935

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

Heat treatment for B50A249 S12

  • Austenitization (All Classes)

    • Forging shall be heated slowly to 1875oF- 1925oF and held at temperature approximately 30 minutes per inch of thickness or diameter, to assure uniform temperature within the load and each part thereof.

  • Quenching
    • B5QA249B

      • Each forging shall be oil quenched to a temperature below 600F. The forging shall then be cooled to a temperature below the Mf temperature (approximately 300F) to assure complete transformation. GE Test Method E50A209 is to be used as a guide for selecting adequate quenching times. Time of immersion in oil, and the maximum surface temperature of the forging during the first ten minutes after removal from the oil shall be reported.

    • B50A249C

      • Forging shall be forced air quenched to a temperature below the Mf temperature (approximately 300F) to assure complete transformation.

  • Tempering (All Classes)

    • Forging shall be double tempered. The first temper shall be at 110OF minimum. The second temper shall be at 11 50F minimum. The forging shall be held at the temperature for one (1) hour per inch of maximum thickness or diameter during the tempering cycle and then cooled uniformly to room temperature.

  • Stress Relief Anneal (SRA)

    • When a stress relief heat treatment is performed, the forging shall be stress relieved at a temperature 50F below the final tempering temperature and shall be still air or furnace cooled.

Thermal Properties

1.4935 High Temperature acc. to EN 10302

  • +QT700

      High Temperature

    • Temp 50 °C - > 465 MPa
    • Temp 100 °C - > 460 MPa
    • Temp 150 °C - > 445 MPa
    • Temp 200 °C - > 430 MPa
    • Temp 250 °C - > 415 MPa
    • Temp 300 °C - > 390 MPa
    • Temp 350 °C - > 380 MPa
    • Temp 400 °C - > 360 MPa
    • Temp 450 °C - > 330 MPa
    • Temp 500 °C - > 290 MPa
    • Temp 550 °C - > 250 MPa
  • +QT800

      High Temperature

    • Temp 50 °C - > 585 MPa
    • Temp100 °C - > 560 MPa
    • Temp 150 °C - > 545 MPa
    • Temp 200 °C - > 530 MPa
    • Temp 250 °C - > 505 MPa
    • Temp 300 °C - > 480 MPa
    • Temp 350 °C - > 450 MPa
    • Temp 400 °C - > 420 MPa
    • Temp 450 °C - > 380 MPa
    • Temp 500 °C - > 335 MPa
    • Temp 550 °C - > 280 MPa

Welding Properties

welding of this material is not straightfor- ward owing to its crack sensitivity.

Machining Properties

Machining

Similar or Equivalents Steel Grade

AISI 422, AISI 616, S42200, 1.4935, X22CrMoWV12-1, SUH616, 20VNiWMoCr120, ,EW 4935, T502, 56B.I., DE 4935, HWMoV3, Grade 616, B50A951 A1, A2, A3, A4, HT9