FabDigitFabDigit

Steel A36 vs S355JR

Steel · grade comparison

Steel A36 and S355JR are both steel grades. S355JR is the stronger of the two: yield strength 400 MPa (58 ksi) against 260 MPa (37.7 ksi) for A36, about 54% more; tensile strength follows at 550 MPa (79.8 ksi) vs 450 MPa (65.3 ksi). S355JR is the more ductile: elongation 25% versus 22% for A36, and S355JR is harder (160 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 45 W/m·K). On the shop floor, A36 welds better (95 vs 85 out of 100).

A36Choose it when the part sees heat, or when it will be welded.

S355JRChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

A36 vs S355JR: properties

A36S355JR

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
550 MPa79.8 ksi

Yield Strength (0.2% offset)

260 MPa37.7 ksi
400 MPa58 ksi

Elongation at Break

22%
25%

Compressive Strength

260 MPa37.7 ksi
400 MPa58 ksi

Shear Strength

275 MPa39.9 ksi
345 MPa50 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
250 MPa36.3 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
50 J36.9 ft·lbf

Hardness, Brinell

120 HB
160 HB

Hardness, Rockwell B

67 HRB
83 HRB

Hardness, Vickers

126 HV
170 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Reduction in Area 50%

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
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

Max Service Temperature (continuous)

400°C752 °F
350°C662 °F

Same in both: Latent Heat of Fusion 247 J/g106 BTU/lb · 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).

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
60 / 100

Machinability Rating (AISI 1212 = 100 %)

72%
58%

Weldability

95 / 100
85 / 100

Formability (cold)

80 / 100
62 / 100

Brazeability / Solderability

70 / 100
60 / 100

Polishability

40 / 100
45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

2 kg CO₂/kg
2.1 kg CO₂/kg

Typical Recycled Content

40%
30%

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

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

57 kN·m/kg
70 kN·m/kg

Specific Stiffness (E / density)

25.5 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

169 kJ/m³
381 kJ/m³

Thermal Diffusivity

13.6 mm²/s
12.2 mm²/s

Same in both: Thermal Shock Resistance Index 10

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 scaleA36S355JR

Manufacturing and finishing

CapabilityA36S355JR
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$ Budget$ Budget
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
E-CoatingYes—
HVOF CoatingYes—
Hot-Dip GalvanizingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

A36 vs S355JR — frequently asked

Is S355JR stronger than A36?

Yes. S355JR has a typical yield strength of 400 MPa (58 ksi) against 260 MPa (37.7 ksi) for A36 — about 54% more. Tensile strength is 550 MPa (79.8 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, A36 or S355JR?

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 S355JR?

A36, by a small margin. Both rate good for machinability — 65/100 against 60/100 for S355JR; for welding the order is A36 first (excellent, 95/100) then S355JR (excellent, 85/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A36 and S355JR 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.