Stainless Steel 1.4640 vs 303
Stainless Steel · grade comparison
Stainless Steel 1.4640 and 303 are both stainless steel grades. 303 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 240 MPa (34.8 ksi) for 1.4640, about 88% more; tensile strength follows at 655 MPa (95 ksi) vs 520 MPa (75.4 ksi). In exchange, 1.4640 is the more ductile: elongation 55% versus 30% for 303, and 303 is harder (240 HB vs 150 HB). On the shop floor, 303 machines more easily (very good vs fair), 1.4640 welds better (very good vs poor), and 1.4640 sits in a lower cost tier (standard, $$) than 303 (premium, $$$).
1.4640Choose it when the part is bent, formed or impact-loaded, or when it will be welded.
303Choose it when strength drives the design, or when the part is machined in volume.
1.4640 vs 303: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all stainless 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 stainless 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.
Bulk Modulus
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
Same in both: Elastic (Young's) Modulus 193 GPa28 Msi · Shear Modulus 77 GPa11.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Liquidus Temperature
Same in both: Density 7.9 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Thermal Conductivity 16.2 W/m·K9.4 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.4 % IACS · Electrical Resistivity 7.2×10⁻⁷ Ω·m28.3 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 %)
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Embodied Water
Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Typical Recycled Content 65%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Same in both: Specific Stiffness (E / density) 24.4 MN·m/kg · Thermal Diffusivity 4.1 mm²/s · Thermal Shock Resistance Index 3
Strength versus weight
Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 1.4640 | 303 |
|---|---|---|
| CNC machining | — | Yes |
| Default condition | — | Cold Drawn |
| Relative cost | $$ Standard | $$$ Premium |
| 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 |
| Electropolishing | — | Yes |
| HVOF Coating | — | Yes |
| MoS2 | — | Yes |
| Multilayer CVD | — | Yes |
| Nickel Plating | — | Yes |
| PTFE Coating | — | Yes |
| Painting | — | Yes |
| Passivation (Stainless Steel) | — | Yes |
They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.
1.4640 vs 303 — frequently asked
Is 303 stronger than 1.4640?
Yes. 303 has a typical yield strength of 450 MPa (65.3 ksi) against 240 MPa (34.8 ksi) for 1.4640 — about 88% more. Tensile strength is 655 MPa (95 ksi) vs 520 MPa (75.4 ksi).
Which is cheaper, 1.4640 or 303?
1.4640 is the lower-cost material: it sits in the standard tier ($$) while 303 is premium ($$$). 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, 1.4640 or 303?
303. Its machinability rates very good (72/100) against fair (40/100) for 1.4640; for welding the order is 1.4640 first (very good, 70/100) then 303 (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 1.4640 and 303 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.