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Steel 1215 vs SUM23

Steel · grade comparison

Steel 1215 and SUM23 are both steel grades, both machining-friendly steel. Both yield at about 250 MPa — strength does not separate them. 1215 is the more ductile: elongation 25% versus 22% for SUM23.

1215Choose it when the part is bent, formed or impact-loaded.

1215 vs SUM23: properties

1215SUM23

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elongation at Break

25%
22%

Shear Strength

290 MPa42.1 ksi
260 MPa37.7 ksi

Fatigue Strength (Endurance Limit)

190 MPa27.6 ksi
180 MPa26.1 ksi

Hardness, Rockwell B

70 HRB
68 HRB

Charpy V-Notch Impact (RT)

—
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 · Tensile Strength (Ultimate) 415 MPa60.2 ksi · Yield Strength (0.2% offset) 250 MPa36.3 ksi · Reduction in Area 45% · Hardness, Brinell 121 HB

Physical

Density and transition temperatures.

Liquidus Temperature

1,510°C2,750 °F
1,500°C2,732 °F

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

Thermal

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

Thermal Conductivity

51.9 W/m·K30 BTU/hr·ft·°F
51 W/m·K29.5 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 486 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · 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

Same in both: Corrosion Resistance 8 / 100

Manufacturability

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

Machinability

85 / 100
90 / 100

Machinability Rating (AISI 1212 = 100 %)

120%
125%

Formability (cold)

35 / 100
55 / 100

Brazeability / Solderability

55 / 100
60 / 100

Same in both: Weldability 20 / 100 · Polishability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

26 MJ/kg11,178 BTU/lb
25 MJ/kg10,748 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
1.9 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

35%
40%

Common Calculations

Ratios derived from the values above.

Thermal Diffusivity

13.6 mm²/s
13.3 mm²/s

Same in both: Specific Strength (UTS / density) 53 kN·m/kg · Specific Stiffness (E / density) 25.4 MN·m/kg · Modulus of Resilience 156 kJ/m³ · 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 scale1215SUM23

Manufacturing and finishing

Capability1215SUM23
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.

1215 vs SUM23 — frequently asked

What is the difference between 1215 and SUM23?

Steel 1215 and SUM23 are both steel grades, both machining-friendly steel. Both yield at about 250 MPa — strength does not separate them. 1215 is the more ductile: elongation 25% versus 22% for SUM23.

Which is cheaper, 1215 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, 1215 or SUM23?

SUM23, by a small margin. Both rate excellent for machinability — 90/100 against 85/100 for 1215.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1215 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.