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Steel A36 vs A656

Steel · grade comparison

Steel A36 and A656 are both steel grades, both structural steel. A656 is the stronger of the two: yield strength 580 MPa (84.1 ksi) against 260 MPa (37.7 ksi) for A36, about 123% more; tensile strength follows at 660 MPa (95.7 ksi) vs 450 MPa (65.3 ksi). In exchange, A36 is the more ductile: elongation 22% versus 16% for A656, and A656 is harder (215 HB vs 120 HB). A36 runs hotter in service (400°C vs 350°C continuous) and A36 conducts heat better (51.9 W/m·K vs 46 W/m·K). On the shop floor, A36 machines more easily (good vs fair) and A36 welds better (excellent vs very good).

A36Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

A656Choose it when strength drives the design.

A36 vs A656: properties

A36A656

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

79.3 GPa11.5 Msi
79 GPa11.5 Msi

Tensile Strength (Ultimate)

450 MPa65.3 ksi
660 MPa95.7 ksi

Yield Strength (0.2% offset)

260 MPa37.7 ksi
580 MPa84.1 ksi

Elongation at Break

22%
16%

Compressive Strength

260 MPa37.7 ksi
580 MPa84.1 ksi

Shear Strength

275 MPa39.9 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
290 MPa42.1 ksi

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
80 J59 ft·lbf

Hardness, Brinell

120 HB
215 HB

Hardness, Rockwell B

67 HRB
96 HRB

Hardness, Vickers

126 HV
225 HV

Hardness, Rockwell C

—
18 HRC

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 50% · Fracture Toughness (K_IC) 100 MPa·√m91 ksi·√in

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,470°C2,678 °F
1,425°C2,597 °F

Liquidus Temperature

1,520°C2,768 °F
1,510°C2,750 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³

Thermal

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

Thermal Conductivity

51.9 W/m·K30 BTU/hr·ft·°F
46 W/m·K26.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

11.7 µm/m·K6.5 µin/in·°F
12 µm/m·K6.7 µin/in·°F

Latent Heat of Fusion

247 J/g106 BTU/lb
270 J/g116 BTU/lb

Max Service Temperature (continuous)

400°C752 °F
350°C662 °F

Min Service Temperature

-20°C-4 °F
-40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

11 % IACS
9 % IACS

Electrical Resistivity

1.6×10⁻⁷ Ω·m6.3 µΩ·in
1.9×10⁻⁷ Ω·m7.48 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.65 V
-0.62 V

Corrosion Resistance

10 / 100
12 / 100

Manufacturability

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

Machinability

65 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

72%
50%

Weldability

95 / 100
75 / 100

Formability (cold)

80 / 100
65 / 100

Brazeability / Solderability

70 / 100
45 / 100

Polishability

40 / 100
45 / 100

Sustainability

Primary-production footprint per kilogram.

Typical Recycled Content

40%
30%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

57 kN·m/kg
84 kN·m/kg

Modulus of Resilience

169 kJ/m³
841 kJ/m³

Thermal Diffusivity

13.6 mm²/s
12.2 mm²/s

Thermal Shock Resistance Index

10
13

Same in both: Specific Stiffness (E / density) 25.5 MN·m/kg

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 scaleA656A36

Manufacturing and finishing

CapabilityA36A656
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 and Sheet metal. 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.

A36 vs A656 — frequently asked

Is A656 stronger than A36?

Yes. A656 has a typical yield strength of 580 MPa (84.1 ksi) against 260 MPa (37.7 ksi) for A36 — about 123% more. Tensile strength is 660 MPa (95.7 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, A36 or A656?

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, A36 or A656?

A36. Its machinability rates good (65/100) against fair (50/100) for A656; for welding the order is A36 first (excellent, 95/100) then A656 (very good, 75/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A36 and A656 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.