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Steel 1117 vs SUM23

Steel · grade comparison

Steel 1117 and SUM23 are both steel grades, both machining-friendly steel. SUM23 is the stronger of the two: yield strength 250 MPa (36.3 ksi) against 235 MPa (34.1 ksi) for 1117, about 6% more. In exchange, 1117 is the more ductile: elongation 33% versus 22% for SUM23. On the shop floor, SUM23 machines more easily (excellent vs very good) and 1117 welds better (fair vs poor).

1117Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

SUM23Choose it when strength drives the design, or when the part is machined in volume.

1117 vs SUM23: properties

1117SUM23

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

425 MPa61.6 ksi
415 MPa60.2 ksi

Yield Strength (0.2% offset)

235 MPa34.1 ksi
250 MPa36.3 ksi

Elongation at Break

33%
22%

Reduction in Area

58%
45%

Shear Strength

320 MPa46.4 ksi
260 MPa37.7 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
180 MPa26.1 ksi

Charpy V-Notch Impact (RT)

50 J36.9 ft·lbf
35 J25.8 ft·lbf

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Brinell 121 HB · Hardness, Rockwell B 68 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.87 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Specific Heat Capacity

470 J/kg·K0.11 BTU/lb·°F
486 J/kg·K0.12 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.7 µm/m·K6.5 µin/in·°F
11.9 µm/m·K6.6 µin/in·°F

Latent Heat of Fusion

250 J/g107 BTU/lb
247 J/g106 BTU/lb

Same in both: Thermal Conductivity 51 W/m·K29.5 BTU/hr·ft·°F · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 10.8 % IACS · Electrical Resistivity 1.6×10⁻⁷ Ω·m6.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.61 V
-0.6 V

Corrosion Resistance

10 / 100
8 / 100

Manufacturability

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

Machinability

70 / 100
90 / 100

Machinability Rating (AISI 1212 = 100 %)

91%
125%

Weldability

50 / 100
20 / 100

Formability (cold)

60 / 100
55 / 100

Brazeability / Solderability

65 / 100
60 / 100

Polishability

45 / 100
40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

45 L/kg5.4 gal/lb
40 L/kg4.8 gal/lb

Typical Recycled Content

30%
40%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

54 kN·m/kg
53 kN·m/kg

Modulus of Resilience

138 kJ/m³
156 kJ/m³

Thermal Diffusivity

13.8 mm²/s
13.3 mm²/s

Same in both: Specific Stiffness (E / density) 25.4 MN·m/kg · Thermal Shock Resistance Index 9

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 scale1117SUM23

Manufacturing and finishing

Capability1117SUM23
Default conditionHRHR
Relative cost$ Budget$ Budget
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining. 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.

1117 vs SUM23 — frequently asked

Is SUM23 stronger than 1117?

Yes. SUM23 has a typical yield strength of 250 MPa (36.3 ksi) against 235 MPa (34.1 ksi) for 1117 — about 6% more. Tensile strength is 415 MPa (60.2 ksi) vs 425 MPa (61.6 ksi).

Which is cheaper, 1117 or SUM23?

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

Which is easier to machine, 1117 or SUM23?

SUM23. Its machinability rates excellent (90/100) against very good (70/100) for 1117; for welding the order is 1117 first (fair, 50/100) then SUM23 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1117 and SUM23 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.