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Steel SUM43-IH vs SUM43-N

Steel · SUM43 temper comparison

SUM43-IH and SUM43-N are two conditions of the same steel grade, SUM43: IH (induction hardened) versus N (normalized). The chemistry is identical, so every difference below comes from the condition. SUM43-IH is the stronger of the two: yield strength 640 MPa (92.8 ksi) against 400 MPa (58 ksi) for SUM43-N, about 60% more; tensile strength follows at 760 MPa (110 ksi) vs 715 MPa (104 ksi). In exchange, SUM43-N is the more ductile: elongation 15% versus 10% for SUM43-IH, and SUM43-IH is harder (560 HB vs 205 HB). SUM43-N runs hotter in service (400°C vs 200°C continuous) and SUM43-N conducts electricity better (9.8 % IACS vs 8.5 % IACS). On the shop floor, SUM43-N machines more easily (very good vs poor) and SUM43-N welds better (poor vs not recommended).

SUM43-IHChoose it when strength drives the design.

SUM43-NChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

SUM43-IH vs SUM43-N: properties

SUM43-IHSUM43-N

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
715 MPa104 ksi

Yield Strength (0.2% offset)

640 MPa92.8 ksi
400 MPa58 ksi

Elongation at Break

10%
15%

Reduction in Area

25%
33%

Compressive Strength

660 MPa95.7 ksi
400 MPa58 ksi

Shear Strength

460 MPa66.7 ksi
430 MPa62.4 ksi

Fatigue Strength (Endurance Limit)

450 MPa65.3 ksi
300 MPa43.5 ksi

Fracture Toughness (K_IC)

32 MPa·√m29.1 ksi·√in
58 MPa·√m52.8 ksi·√in

Charpy V-Notch Impact (RT)

10 J7.4 ft·lbf
22 J16.2 ft·lbf

Hardness, Brinell

560 HB
205 HB

Hardness, Rockwell B

95 HRB
94 HRB

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,490°C2,714 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
49 W/m·K28.3 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
400°C752 °F

Same in both: Specific Heat Capacity 480 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.5 % IACS
9.8 % IACS

Electrical Resistivity

2×10⁻⁷ Ω·m7.87 µΩ·in
1.75×10⁻⁷ Ω·m6.89 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

20 / 100
74 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
74%

Weldability

10 / 100
25 / 100

Formability (cold)

5 / 100
35 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 30%

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 scaleSUM43

SUM43-IH vs SUM43-N — frequently asked

Is SUM43-IH stronger than SUM43-N?

Yes. SUM43-IH has a typical yield strength of 640 MPa (92.8 ksi) against 400 MPa (58 ksi) for SUM43-N — about 60% more. Tensile strength is 760 MPa (110 ksi) vs 715 MPa (104 ksi).

Which condition does FabDigit quote by default, IH or N?

CD is the default SUM43 condition in the FabDigit quote flow (neither IH nor N). 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, SUM43-IH or SUM43-N?

SUM43-N. Its machinability rates very good (74/100) against poor (20/100) for SUM43-IH; for welding the order is SUM43-N first (poor, 25/100) then SUM43-IH (not recommended, 10/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in SUM43-IH and SUM43-N 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.