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Steel A36 vs S235JR

Steel · grade comparison

Steel A36 and S235JR are both steel grades, both structural steel. A36 is the stronger of the two: tensile strength 450 MPa (65.3 ksi) against 420 MPa (60.9 ksi) for S235JR, about 7% more. In exchange, S235JR is the more ductile: elongation 26% versus 22% for A36. A36 runs hotter in service (400°C vs 350°C continuous).

A36Choose it when strength drives the design, or when the part sees heat.

S235JRChoose it when the part is bent, formed or impact-loaded.

A36 vs S235JR: properties

A36S235JR

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
420 MPa60.9 ksi

Elongation at Break

22%
26%

Reduction in Area

50%
55%

Compressive Strength

260 MPa37.7 ksi
255 MPa37 ksi

Shear Strength

275 MPa39.9 ksi
260 MPa37.7 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
170 MPa24.7 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
80 MPa·√m72.8 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
40 J29.5 ft·lbf

Hardness, Vickers

126 HV
125 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Yield Strength (0.2% offset) 260 MPa37.7 ksi · Hardness, Brinell 120 HB · Hardness, Rockwell B 67 HRB

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,470°C2,678 °F
1,425°C2,597 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Liquidus Temperature 1,520°C2,768 °F

Thermal

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

Thermal Conductivity

51.9 W/m·K30 BTU/hr·ft·°F
50 W/m·K28.9 BTU/hr·ft·°F

Specific Heat Capacity

486 J/kg·K0.12 BTU/lb·°F
460 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
0°C32 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 11 % 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)

-0.65 V
-0.61 V

Same in both: Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

65 / 100
66 / 100

Machinability Rating (AISI 1212 = 100 %)

72%
65%

Formability (cold)

80 / 100
85 / 100

Brazeability / Solderability

70 / 100
80 / 100

Polishability

40 / 100
55 / 100

Castability

—
40 / 100

Same in both: Weldability 95 / 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
54 kN·m/kg

Specific Stiffness (E / density)

25.5 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

169 kJ/m³
161 kJ/m³

Thermal Diffusivity

13.6 mm²/s
13.8 mm²/s

Thermal Shock Resistance Index

10
8

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 scaleA36S235JR

Manufacturing and finishing

CapabilityA36S235JR
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 S235JR — frequently asked

Is A36 stronger than S235JR?

Yes. A36 has a typical tensile strength of 450 MPa (65.3 ksi) against 420 MPa (60.9 ksi) for S235JR — about 7% more.

Which is cheaper, A36 or S235JR?

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.

When should I choose A36 over S235JR?

Pick A36 when strength drives the design, or when the part sees heat. Pick S235JR when the part is bent, formed or impact-loaded.

Ready to make it?

Upload a CAD file and FabDigit prices the part in A36 and S235JR 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.