FabDigitFabDigit

Steel Supermalloy-H vs Supermalloy-M

Steel · Supermalloy temper comparison

Supermalloy-H and Supermalloy-M are two conditions of the same steel grade, Supermalloy: H (hardened) versus M (thermomechanically controlled processed). The chemistry is identical, so every difference below comes from the condition. Supermalloy-H is the stronger of the two: yield strength 850 MPa (123 ksi) against 230 MPa (33.4 ksi) for Supermalloy-M, about 3.7 times as much; tensile strength follows at 950 MPa (138 ksi) vs 560 MPa (81.2 ksi). In exchange, Supermalloy-M is the more ductile: elongation 40% versus 4% for Supermalloy-H, and Supermalloy-H is harder (225 HB vs 115 HB). Supermalloy-M runs hotter in service (400°C vs 250°C continuous). On the shop floor, Supermalloy-H machines more easily (fair vs poor) and Supermalloy-M welds better (good vs fair).

Supermalloy-HChoose it when strength drives the design, or when the part is machined in volume.

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

Supermalloy-H vs Supermalloy-M: properties

Supermalloy-HSupermalloy-M

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

215 GPa31.2 Msi
210 GPa30.5 Msi

Tensile Strength (Ultimate)

950 MPa138 ksi
560 MPa81.2 ksi

Yield Strength (0.2% offset)

850 MPa123 ksi
230 MPa33.4 ksi

Elongation at Break

4%
40%

Reduction in Area

15%
70%

Shear Strength

580 MPa84.1 ksi
360 MPa52.2 ksi

Fatigue Strength (Endurance Limit)

400 MPa58 ksi
250 MPa36.3 ksi

Charpy V-Notch Impact (RT)

35 J25.8 ft·lbf
180 J133 ft·lbf

Hardness, Brinell

225 HB
115 HB

Hardness, Rockwell B

99 HRB
65 HRB

Hardness, Vickers

240 HV
120 HV

Same in both: Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 175 GPa25.4 Msi · Poisson's Ratio 0.31

Physical

Density and transition temperatures.

Same in both: Density 8.77 g/cm³0.32 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F

Thermal

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

Thermal Conductivity

18 W/m·K10.4 BTU/hr·ft·°F
19 W/m·K11 BTU/hr·ft·°F

Max Service Temperature (continuous)

250°C482 °F
400°C752 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.5 µm/m·K6.9 µin/in·°F · Latent Heat of Fusion 290 J/g125 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.8 % IACS
2.9 % IACS

Electrical Resistivity

6.2×10⁻⁷ Ω·m24.4 µΩ·in
6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.2 V · Corrosion Resistance 45 / 100

Manufacturability

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

Machinability

38 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

34%
25%

Weldability

45 / 100
60 / 100

Formability (cold)

30 / 100
85 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 65 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 135 MJ/kg58,040 BTU/lb · Embodied Carbon (primary production) 10.5 kg CO₂/kg · Embodied Water 200 L/kg24 gal/lb · Typical Recycled Content 25%

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 scaleSupermalloy

Supermalloy-H vs Supermalloy-M — frequently asked

Is Supermalloy-H stronger than Supermalloy-M?

Yes. Supermalloy-H has a typical yield strength of 850 MPa (123 ksi) against 230 MPa (33.4 ksi) for Supermalloy-M — about 3.7 times as much. Tensile strength is 950 MPa (138 ksi) vs 560 MPa (81.2 ksi).

Which condition does FabDigit quote by default, H or M?

M is the default Supermalloy condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, Supermalloy-H or Supermalloy-M?

Supermalloy-H. Its machinability rates fair (38/100) against poor (28/100) for Supermalloy-M; for welding the order is Supermalloy-M first (good, 60/100) then Supermalloy-H (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Supermalloy-H and Supermalloy-M 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.