Steel 45# vs AR500
Steel · grade comparison
Steel 45# and AR500 are both steel grades. AR500 is the stronger of the two: yield strength 1,350 MPa (196 ksi) against 530 MPa (76.9 ksi) for 45#, about 155% more; tensile strength follows at 1,650 MPa (239 ksi) vs 625 MPa (90.6 ksi). In exchange, 45# is the more ductile: elongation 12% versus 9% for AR500, and AR500 is harder (500 HB vs 179 HB). 45# runs hotter in service (425°C vs 250°C continuous) and 45# conducts heat better (49 W/m·K vs 40 W/m·K). On the shop floor, 45# machines more easily (good vs not recommended) and 45# sits in a lower cost tier (budget, $) than AR500 (high, $$$$).
45#Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
AR500Choose it when strength drives the design.
45# vs AR500: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Hardness, Rockwell C
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Liquidus Temperature
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
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 25%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 26.1 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.
Manufacturing and finishing
| Capability | 45# | AR500 |
|---|---|---|
| Default condition | CD | Q&T |
| Relative cost | $ Budget | $$$$ High |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 1.6 µm |
Both are offered for CNC machining and Sheet metal. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.
45# vs AR500 — frequently asked
Is AR500 stronger than 45#?
Yes. AR500 has a typical yield strength of 1,350 MPa (196 ksi) against 530 MPa (76.9 ksi) for 45# — about 155% more. Tensile strength is 1,650 MPa (239 ksi) vs 625 MPa (90.6 ksi).
Which is cheaper, 45# or AR500?
45# is the lower-cost material: it sits in the budget tier ($) while AR500 is high ($$$$). 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, 45# or AR500?
45#. Its machinability rates good (56/100) against not recommended (12/100) for AR500.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 45# 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.