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Steel A2 vs SKS3

Steel · grade comparison

Steel A2 and SKS3 are both steel grades, both tool steel. Both yield at about 470 MPa — strength does not separate them. A2 is the more ductile: elongation 22% versus 18% for SKS3, and A2 is harder (217 HB vs 200 HB). A2 runs hotter in service (425°C vs 200°C continuous) and SKS3 conducts heat better (33 W/m·K vs 26 W/m·K).

A2Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

A2 vs SKS3: properties

A2SKS3

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

203 GPa29.4 Msi
210 GPa30.5 Msi

Shear Modulus

78 GPa11.3 Msi
80 GPa11.6 Msi

Poisson's Ratio

0.28
0.29

Tensile Strength (Ultimate)

740 MPa107 ksi
750 MPa109 ksi

Yield Strength (0.2% offset)

470 MPa68.2 ksi
450 MPa65.3 ksi

Elongation at Break

22%
18%

Reduction in Area

45%
35%

Compressive Strength

500 MPa72.5 ksi
—

Shear Strength

450 MPa65.3 ksi
470 MPa68.2 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
340 MPa49.3 ksi

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

217 HB
200 HB

Hardness, Rockwell B

96 HRB
94 HRB

Hardness, Vickers

230 HV
210 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi

Physical

Density and transition temperatures.

Density

7.86 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Liquidus Temperature

1,465°C2,669 °F
1,470°C2,678 °F

Same in both: Melting Point (Solidus) 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

26 W/m·K15 BTU/hr·ft·°F
33 W/m·K19.1 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.7 µm/m·K5.9 µin/in·°F
12.5 µm/m·K6.9 µin/in·°F

Max Service Temperature (continuous)

425°C797 °F
200°C392 °F

Min Service Temperature

-30°C-22 °F
-20°C-4 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

2.7 % IACS
7 % IACS

Electrical Resistivity

6.5×10⁻⁷ Ω·m25.6 µΩ·in
2.5×10⁻⁷ Ω·m9.84 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

20 / 100
15 / 100

Manufacturability

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

Machinability

45 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
45%

Weldability

20 / 100
12 / 100

Formability (cold)

35 / 100
25 / 100

Castability

20 / 100
—

Polishability

70 / 100
80 / 100

Same in both: Brazeability / Solderability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

36 MJ/kg15,477 BTU/lb
34 MJ/kg14,617 BTU/lb

Embodied Carbon (primary production)

2.6 kg CO₂/kg
2.4 kg CO₂/kg

Embodied Water

65 L/kg7.8 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

35%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

94 kN·m/kg
96 kN·m/kg

Specific Stiffness (E / density)

25.8 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

544 kJ/m³
482 kJ/m³

Thermal Diffusivity

7.2 mm²/s
9.1 mm²/s

Same in both: 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 scaleA2SKS3

Manufacturing and finishing

CapabilityA2SKS3
Default conditionAnnealedAnnealed
Relative cost$$$ Premium$$$ Premium
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.

A2 vs SKS3 — frequently asked

What is the difference between A2 and SKS3?

Steel A2 and SKS3 are both steel grades, both tool steel. Both yield at about 470 MPa — strength does not separate them. A2 is the more ductile: elongation 22% versus 18% for SKS3, and A2 is harder (217 HB vs 200 HB).

Which is cheaper, A2 or SKS3?

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

Which is easier to machine, A2 or SKS3?

SKS3, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for A2; for welding the order is A2 first (poor, 20/100) then SKS3 (not recommended, 12/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A2 and SKS3 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.