Steel A3 vs D1
Steel · grade comparison
Steel A3 and D1 are both steel grades. Both yield at about 430 MPa — strength does not separate them. A3 is the more ductile: elongation 20% versus 16% for D1, and D1 is harder (235 HB vs 217 HB). A3 conducts heat better (24 W/m·K vs 20 W/m·K). On the shop floor, D1 sits in a lower cost tier (standard, $$) than A3 (premium, $$$).
A3Choose it when the part is bent, formed or impact-loaded.
D1Choose it when cost is the deciding factor.
A3 vs D1: 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.
Elastic (Young's) Modulus
Shear Modulus
Poisson's Ratio
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Hardness, Brinell
Hardness, Rockwell B
Hardness, Rockwell C
Hardness, Vickers
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Same in both: Bulk Modulus 160 GPa23.2 Msi · Tensile Strength (Ultimate) 760 MPa110 ksi · Compressive Strength 900 MPa131 ksi · Charpy V-Notch Impact (RT) 25 J18.4 ft·lbf
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Max Service Temperature (continuous) 200°C392 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.7 % IACS · Electrical Resistivity 6.5×10⁻⁷ Ω·m25.6 µΩ·in
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 %)
Castability
Same in both: Weldability 15 / 100 · Formability (cold) 20 / 100 · Brazeability / Solderability 35 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 2.6 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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 | A3 | D1 |
|---|---|---|
| CNC machining | Yes | — |
| Default condition | — | — |
| Relative cost | $$$ Premium | $$ Standard |
| 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.
A3 vs D1 — frequently asked
What is the difference between A3 and D1?
Steel A3 and D1 are both steel grades. Both yield at about 430 MPa — strength does not separate them. A3 is the more ductile: elongation 20% versus 16% for D1, and D1 is harder (235 HB vs 217 HB).
Which is cheaper, A3 or D1?
D1 is the lower-cost material: it sits in the standard tier ($$) while A3 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
When should I choose A3 over D1?
Pick A3 when the part is bent, formed or impact-loaded. Pick D1 when cost is the deciding factor.
Ready to make it?
Upload a CAD file and FabDigit prices the part in A3 and D1 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.