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Stainless Steel SUS440C-A vs SUS440C-H

Stainless Steel · SUS440C temper comparison

SUS440C-A and SUS440C-H are two conditions of the same stainless steel grade, SUS440C: A (solution annealed) versus H (hardened). The chemistry is identical, so every difference below comes from the condition. SUS440C-H is the stronger of the two: yield strength 1,900 MPa (276 ksi) against 450 MPa (65.3 ksi) for SUS440C-A, about 4.2 times as much; tensile strength follows at 2,030 MPa (294 ksi) vs 760 MPa (110 ksi). In exchange, SUS440C-A is the more ductile: elongation 14% versus 1% for SUS440C-H, and SUS440C-H is harder (620 HB vs 240 HB). SUS440C-A runs hotter in service (600°C vs 150°C continuous). On the shop floor, SUS440C-A machines more easily (fair vs not recommended) and SUS440C-A welds better (poor vs not recommended).

SUS440C-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

SUS440C-HChoose it when strength drives the design.

SUS440C-A vs SUS440C-H: properties

SUS440C-ASUS440C-H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
2,030 MPa294 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
1,900 MPa276 ksi

Elongation at Break

14%
1%

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
5 J3.7 ft·lbf

Hardness, Brinell

240 HB
620 HB

Hardness, Rockwell C

22 HRC
61 HRC

Hardness, Vickers

250 HV
730 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 78 GPa11.3 Msi · Bulk Modulus 166 GPa24.1 Msi · Poisson's Ratio 0.28 · Reduction in Area 25% · Shear Strength 460 MPa66.7 ksi · Fatigue Strength (Endurance Limit) 350 MPa50.8 ksi · Hardness, Rockwell B 99 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.68 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,370°C2,498 °F · Liquidus Temperature 1,480°C2,696 °F

Thermal

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

Max Service Temperature (continuous)

600°C1,112 °F
150°C302 °F

Same in both: Thermal Conductivity 24.2 W/m·K14 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.2 µm/m·K5.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -70°C-94 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.9 % IACS · Electrical Resistivity 6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

42 / 100
48 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.25 V

Manufacturability

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

Machinability

35 / 100
5 / 100

Weldability

15 / 100
5 / 100

Formability (cold)

20 / 100
2 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 40% · Brazeability / Solderability 40 / 100 · Polishability 85 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 5 kg CO₂/kg · Embodied Water 220 L/kg26.4 gal/lb · Typical Recycled Content 45%

Strength versus weight

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

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scaleSUS440C

SUS440C-A vs SUS440C-H — frequently asked

Is SUS440C-H stronger than SUS440C-A?

Yes. SUS440C-H has a typical yield strength of 1,900 MPa (276 ksi) against 450 MPa (65.3 ksi) for SUS440C-A — about 4.2 times as much. Tensile strength is 2,030 MPa (294 ksi) vs 760 MPa (110 ksi).

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

A is the default SUS440C 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, SUS440C-A or SUS440C-H?

SUS440C-A. Its machinability rates fair (35/100) against not recommended (5/100) for SUS440C-H; for welding the order is SUS440C-A first (poor, 15/100) then SUS440C-H (not recommended, 5/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in SUS440C-A and SUS440C-H 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.