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Steel A36 vs S355J2

Steel · grade comparison

Steel A36 and S355J2 are both steel grades, both structural steel. S355J2 is the stronger of the two: yield strength 390 MPa (56.6 ksi) against 260 MPa (37.7 ksi) for A36, about 50% more; tensile strength follows at 520 MPa (75.4 ksi) vs 450 MPa (65.3 ksi). S355J2 is harder — 170 HB against 120 HB for A36 — which matters for wear surfaces and threads. A36 conducts heat better (51.9 W/m·K vs 45 W/m·K). On the shop floor, A36 machines more easily (65 vs 55 out of 100) and A36 forms better (very good vs good).

A36Choose it when the part is machined in volume.

S355J2Choose it when strength drives the design, or when surface hardness matters.

A36 vs S355J2: properties

A36S355J2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
210 GPa30.5 Msi

Shear Modulus

79.3 GPa11.5 Msi
81 GPa11.7 Msi

Poisson's Ratio

0.29
0.3

Tensile Strength (Ultimate)

450 MPa65.3 ksi
520 MPa75.4 ksi

Yield Strength (0.2% offset)

260 MPa37.7 ksi
390 MPa56.6 ksi

Elongation at Break

22%
24%

Compressive Strength

260 MPa37.7 ksi
390 MPa56.6 ksi

Shear Strength

275 MPa39.9 ksi
320 MPa46.4 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
250 MPa36.3 ksi

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
90 J66.4 ft·lbf

Hardness, Brinell

120 HB
170 HB

Hardness, Rockwell B

67 HRB
86 HRB

Hardness, Vickers

126 HV
180 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · 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
1,505°C2,741 °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
45 W/m·K26 BTU/hr·ft·°F

Specific Heat Capacity

486 J/kg·K0.12 BTU/lb·°F
470 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

Same in both: Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °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).

Corrosion Resistance

10 / 100
12 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.65 V

Manufacturability

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

Machinability

65 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

72%
62%

Weldability

95 / 100
88 / 100

Formability (cold)

80 / 100
65 / 100

Brazeability / Solderability

70 / 100
55 / 100

Same in both: Polishability 40 / 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
66 kN·m/kg

Specific Stiffness (E / density)

25.5 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

169 kJ/m³
362 kJ/m³

Thermal Diffusivity

13.6 mm²/s
12.2 mm²/s

Thermal Shock Resistance Index

10
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 scaleA36S355J2

Manufacturing and finishing

CapabilityA36S355J2
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 S355J2 — frequently asked

Is S355J2 stronger than A36?

Yes. S355J2 has a typical yield strength of 390 MPa (56.6 ksi) against 260 MPa (37.7 ksi) for A36 — about 50% more. Tensile strength is 520 MPa (75.4 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, A36 or S355J2?

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 S355J2?

A36, by a small margin. Both rate good for machinability — 65/100 against 55/100 for S355J2; for welding the order is A36 first (excellent, 95/100) then S355J2 (excellent, 88/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A36 and S355J2 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.