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Steel A335 P91 vs H13

Steel · grade comparison

Steel A335 P91 and H13 are both steel grades, both heat resistant steel. A335 P91 is the stronger of the two: yield strength 700 MPa (102 ksi) against 520 MPa (75.4 ksi) for H13, about 35% more; tensile strength follows at 950 MPa (138 ksi) vs 760 MPa (110 ksi). In exchange, H13 is the more ductile: elongation 25% versus 14% for A335 P91, and A335 P91 is harder (300 HB vs 205 HB). H13 runs hotter in service (400°C vs 200°C continuous). On the shop floor, H13 machines more easily (fair vs poor), H13 welds better (fair vs poor), and A335 P91 sits in a lower cost tier (standard, $$) than H13 (high, $$$$).

A335 P91Choose it when strength drives the design, or when cost is the deciding factor.

H13Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

A335 P91 vs H13: properties

A335 P91H13

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

218 GPa31.6 Msi
210 GPa30.5 Msi

Shear Modulus

84 GPa12.2 Msi
81 GPa11.7 Msi

Bulk Modulus

180 GPa26.1 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

950 MPa138 ksi
760 MPa110 ksi

Yield Strength (0.2% offset)

700 MPa102 ksi
520 MPa75.4 ksi

Elongation at Break

14%
25%

Reduction in Area

65%
50%

Compressive Strength

490 MPa71.1 ksi
550 MPa79.8 ksi

Shear Strength

400 MPa58 ksi
480 MPa69.6 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
360 MPa52.2 ksi

Fracture Toughness (K_IC)

120 MPa·√m109 ksi·√in
—

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

300 HB
205 HB

Hardness, Rockwell C

31 HRC
—

Hardness, Vickers

225 HV
215 HV

Hardness, Rockwell B

—
95 HRB

Same in both: Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,450°C2,642 °F
1,425°C2,597 °F

Liquidus Temperature

1,505°C2,741 °F
1,480°C2,696 °F

Thermal

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

Thermal Conductivity

26 W/m·K15 BTU/hr·ft·°F
24.5 W/m·K14.2 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

10.8 µm/m·K6 µin/in·°F
10.9 µm/m·K6.1 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
400°C752 °F

Same in both: Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
5.2×10⁻⁷ Ω·m20.5 µΩ·in

Electrical Conductivity

—
3.3 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.55 V
-0.58 V

Corrosion Resistance

28 / 100
22 / 100

Manufacturability

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

Machinability

25 / 100
45 / 100

Weldability

20 / 100
35 / 100

Formability (cold)

15 / 100
20 / 100

Brazeability / Solderability

35 / 100
30 / 100

Polishability

55 / 100
78 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 50%

Sustainability

Primary-production footprint per kilogram.

Embodied Water

65 L/kg7.8 gal/lb
75 L/kg9 gal/lb

Typical Recycled Content

30%
45%

Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.6 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

122 kN·m/kg
97 kN·m/kg

Specific Stiffness (E / density)

28.1 MN·m/kg
26.9 MN·m/kg

Modulus of Resilience

1,124 kJ/m³
644 kJ/m³

Thermal Diffusivity

7 mm²/s
6.8 mm²/s

Thermal Shock Resistance Index

10
8

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 scaleH13A335 P91

Manufacturing and finishing

CapabilityA335 P91H13
Sheet metalYes—
3D printing—Yes
Default conditionHRAnnealed
Relative cost$$ Standard$$$$ High
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm
Passivated (Metal AM)—Yes
Plated (Metal AM)—Yes

Both are offered for CNC machining. They share 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 P91 vs H13 — frequently asked

Is A335 P91 stronger than H13?

Yes. A335 P91 has a typical yield strength of 700 MPa (102 ksi) against 520 MPa (75.4 ksi) for H13 — about 35% more. Tensile strength is 950 MPa (138 ksi) vs 760 MPa (110 ksi).

Which is cheaper, A335 P91 or H13?

A335 P91 is the lower-cost material: it sits in the standard tier ($$) while H13 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, A335 P91 or H13?

H13. Its machinability rates fair (45/100) against poor (25/100) for A335 P91; for welding the order is H13 first (fair, 35/100) then A335 P91 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A335 P91 and H13 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.