Stainless Steel 304Cu-1/4 Hard vs 304Cu Annealed
Stainless Steel · 304Cu temper comparison
304Cu-1/4 Hard and 304Cu Annealed are two conditions of the same stainless steel grade, 304Cu: 1/4 Hard (quarter hard) versus Annealed. The chemistry is identical, so every difference below comes from the condition. 304Cu-1/4 Hard is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 210 MPa (30.5 ksi) for 304Cu Annealed, about 162% more; tensile strength follows at 860 MPa (125 ksi) vs 500 MPa (72.5 ksi). In exchange, 304Cu Annealed is the more ductile: elongation 55% versus 12% for 304Cu-1/4 Hard, and 304Cu-1/4 Hard is harder (250 HB vs 145 HB). 304Cu Annealed runs hotter in service (750°C vs 300°C continuous).
304Cu-1/4 HardChoose it when strength drives the design.
304Cu AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
304Cu-1/4 Hard vs 304Cu Annealed: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
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 · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Same in both: Density 7.93 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,440°C2,624 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
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 · Thermal Expansion (CTE, 20–100 °C) 17.3 µm/m·K9.6 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Same in both: Electrical Conductivity 2.4 % IACS
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.05 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Brazeability / Solderability 70 / 100 · Polishability 82 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 55 MJ/kg23,646 BTU/lb · Embodied Carbon (primary production) 4.5 kg CO₂/kg · Embodied Water 130 L/kg15.6 gal/lb · Typical Recycled Content 65%
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.
304Cu-1/4 Hard vs 304Cu Annealed — frequently asked
Is 304Cu-1/4 Hard stronger than 304Cu Annealed?
Yes. 304Cu-1/4 Hard has a typical yield strength of 550 MPa (79.8 ksi) against 210 MPa (30.5 ksi) for 304Cu Annealed — about 162% more. Tensile strength is 860 MPa (125 ksi) vs 500 MPa (72.5 ksi).
Which condition does FabDigit quote by default, 1/4 Hard or Annealed?
Annealed is the default 304Cu condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which is easier to machine, 304Cu-1/4 Hard or 304Cu Annealed?
304Cu-1/4 Hard, by a small margin. Both rate fair for machinability — 50/100 against 42/100 for 304Cu Annealed; for welding the order is 304Cu Annealed first (very good, 72/100) then 304Cu-1/4 Hard (good, 65/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 304Cu-1/4 Hard and 304Cu Annealed 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.