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Steel A335 P22 vs A335 P91

Steel · grade comparison

Steel A335 P22 and A335 P91 are both steel grades, both heat resistant steel. A335 P91 is the stronger of the two: yield strength 700 MPa (102 ksi) against 350 MPa (50.8 ksi) for A335 P22, about 100% more; tensile strength follows at 950 MPa (138 ksi) vs 550 MPa (79.8 ksi). In exchange, A335 P22 is the more ductile: elongation 24% versus 14% for A335 P91, and A335 P91 is harder (300 HB vs 165 HB). A335 P91 is stiffer (218 GPa vs 207 GPa) and A335 P22 runs hotter in service (550°C vs 200°C continuous). On the shop floor, A335 P22 machines more easily (fair vs poor) and A335 P22 welds better (fair vs poor).

A335 P22Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

A335 P91Choose it when strength drives the design.

A335 P22 vs A335 P91: properties

A335 P22A335 P91

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

207 GPa30 Msi
218 GPa31.6 Msi

Shear Modulus

80 GPa11.6 Msi
84 GPa12.2 Msi

Bulk Modulus

160 GPa23.2 Msi
180 GPa26.1 Msi

Poisson's Ratio

0.29
0.3

Tensile Strength (Ultimate)

550 MPa79.8 ksi
950 MPa138 ksi

Yield Strength (0.2% offset)

350 MPa50.8 ksi
700 MPa102 ksi

Elongation at Break

24%
14%

Reduction in Area

55%
65%

Compressive Strength

355 MPa51.5 ksi
490 MPa71.1 ksi

Shear Strength

360 MPa52.2 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

255 MPa37 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
120 MPa·√m109 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

165 HB
300 HB

Hardness, Rockwell B

85 HRB
—

Hardness, Rockwell C

12 HRC
31 HRC

Hardness, Vickers

173 HV
225 HV

Physical

Density and transition temperatures.

Density

7.85 g/cm³0.28 lb/in³
7.77 g/cm³0.28 lb/in³

Liquidus Temperature

1,510°C2,750 °F
1,505°C2,741 °F

Same in both: Melting Point (Solidus) 1,450°C2,642 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

37 W/m·K21.4 BTU/hr·ft·°F
26 W/m·K15 BTU/hr·ft·°F

Specific Heat Capacity

460 J/kg·K0.11 BTU/lb·°F
480 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12.4 µm/m·K6.9 µin/in·°F
10.8 µm/m·K6 µin/in·°F

Max Service Temperature (continuous)

550°C1,022 °F
200°C392 °F

Same in both: Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

7.8 % IACS
—

Electrical Resistivity

2.2×10⁻⁷ Ω·m8.66 µΩ·in
6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.55 V

Corrosion Resistance

18 / 100
28 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

50 / 100
25 / 100

Machinability Rating (AISI 1212 = 100 %)

52%
50%

Weldability

50 / 100
20 / 100

Formability (cold)

48 / 100
15 / 100

Brazeability / Solderability

45 / 100
35 / 100

Same in both: Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

33 MJ/kg14,187 BTU/lb
34 MJ/kg14,617 BTU/lb

Embodied Carbon (primary production)

2.4 kg CO₂/kg
2.6 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
65 L/kg7.8 gal/lb

Same in both: Typical Recycled Content 30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

70 kN·m/kg
122 kN·m/kg

Specific Stiffness (E / density)

26.4 MN·m/kg
28.1 MN·m/kg

Modulus of Resilience

296 kJ/m³
1,124 kJ/m³

Thermal Diffusivity

10.2 mm²/s
7 mm²/s

Thermal Shock Resistance Index

8
10

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleA335 P91A335 P22

Manufacturing and finishing

CapabilityA335 P22A335 P91
Default conditionHRHR
Relative cost$$ Standard$$ Standard
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.

A335 P22 vs A335 P91 — frequently asked

Is A335 P91 stronger than A335 P22?

Yes. A335 P91 has a typical yield strength of 700 MPa (102 ksi) against 350 MPa (50.8 ksi) for A335 P22 — about 100% more. Tensile strength is 950 MPa (138 ksi) vs 550 MPa (79.8 ksi).

Which is cheaper, A335 P22 or A335 P91?

Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, A335 P22 or A335 P91?

A335 P22. Its machinability rates fair (50/100) against poor (25/100) for A335 P91; for welding the order is A335 P22 first (fair, 50/100) then A335 P91 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A335 P22 and A335 P91 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.