FabDigitFabDigit

Steel A231 vs AR500

Steel · grade comparison

Steel A231 and AR500 are both steel grades. AR500 is the stronger of the two: tensile strength 1,650 MPa (239 ksi) against 1,550 MPa (225 ksi) for A231, about 6% more. AR500 is harder — 500 HB against 440 HB for A231 — which matters for wear surfaces and threads. AR500 runs hotter in service (250°C vs 220°C continuous). On the shop floor, A231 machines more easily (poor vs not recommended), AR500 welds better (fair vs poor), and A231 forms better (30 vs 15 out of 100).

A231Choose it when the part is machined in volume, or when cost is the deciding factor.

AR500Choose it when strength drives the design, or when surface hardness matters.

A231 vs AR500: properties

A231AR500

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

207 GPa30 Msi
205 GPa29.7 Msi

Shear Modulus

79.3 GPa11.5 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

1,550 MPa225 ksi
1,650 MPa239 ksi

Yield Strength (0.2% offset)

1,400 MPa203 ksi
1,350 MPa196 ksi

Reduction in Area

42%
30%

Shear Strength

960 MPa139 ksi
1,000 MPa145 ksi

Fracture Toughness (K_IC)

45 MPa·√m41 ksi·√in
50 MPa·√m45.5 ksi·√in

Charpy V-Notch Impact (RT)

15 J11.1 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

440 HB
500 HB

Hardness, Rockwell C

46 HRC
50 HRC

Hardness, Vickers

465 HV
525 HV

Compressive Strength

—
1,400 MPa203 ksi

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Elongation at Break 9% · Fatigue Strength (Endurance Limit) 700 MPa102 ksi

Physical

Density and transition temperatures.

Liquidus Temperature

1,490°C2,714 °F
1,500°C2,732 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F

Thermal

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

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
40 W/m·K23.1 BTU/hr·ft·°F

Specific Heat Capacity

475 J/kg·K0.11 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12.2 µm/m·K6.8 µin/in·°F
12 µm/m·K6.7 µin/in·°F

Latent Heat of Fusion

250 J/g107 BTU/lb
270 J/g116 BTU/lb

Max Service Temperature (continuous)

220°C428 °F
250°C482 °F

Same in both: Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 7.5 % IACS · Electrical Resistivity 2.3×10⁻⁷ Ω·m9.06 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.62 V

Corrosion Resistance

14 / 100
13 / 100

Manufacturability

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

Machinability

22 / 100
12 / 100

Machinability Rating (AISI 1212 = 100 %)

25%
10%

Weldability

22 / 100
45 / 100

Formability (cold)

30 / 100
15 / 100

Brazeability / Solderability

35 / 100
—

Polishability

60 / 100
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

34 MJ/kg14,617 BTU/lb
30 MJ/kg12,898 BTU/lb

Embodied Water

60 L/kg7.2 gal/lb
55 L/kg6.6 gal/lb

Same in both: Embodied Carbon (primary production) 2.3 kg CO₂/kg · Typical Recycled Content 25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

197 kN·m/kg
210 kN·m/kg

Specific Stiffness (E / density)

26.4 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

4,734 kJ/m³
4,445 kJ/m³

Thermal Diffusivity

11.8 mm²/s
10.8 mm²/s

Same in both: Thermal Shock Resistance Index 27

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 scaleAR500A231

Manufacturing and finishing

CapabilityA231AR500
CNC machining—Yes
Sheet metal—Yes
Default condition—Q&T
Relative cost$$ Standard$$$$ High
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

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

A231 vs AR500 — frequently asked

Is AR500 stronger than A231?

Yes. AR500 has a typical tensile strength of 1,650 MPa (239 ksi) against 1,550 MPa (225 ksi) for A231 — about 6% more.

Which is cheaper, A231 or AR500?

A231 is the lower-cost material: it sits in the standard tier ($$) while AR500 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, A231 or AR500?

A231. Its machinability rates poor (22/100) against not recommended (12/100) for AR500; for welding the order is AR500 first (fair, 45/100) then A231 (poor, 22/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A231 and AR500 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.