Stainless Steel 347-1/2 Hard vs 347-1/4 Hard
Stainless Steel · 347 temper comparison
347-1/2 Hard and 347-1/4 Hard are two conditions of the same stainless steel grade, 347: 1/2 Hard (half hard) versus 1/4 Hard (quarter hard). The chemistry is identical, so every difference below comes from the condition. 347-1/2 Hard is the stronger of the two: yield strength 790 MPa (115 ksi) against 550 MPa (79.8 ksi) for 347-1/4 Hard, about 44% more; tensile strength follows at 1,035 MPa (150 ksi) vs 900 MPa (131 ksi). In exchange, 347-1/4 Hard is the more ductile: elongation 12% versus 9% for 347-1/2 Hard, and 347-1/2 Hard is harder (310 HB vs 240 HB). 347-1/4 Hard runs hotter in service (425°C vs 370°C continuous). On the shop floor, 347-1/4 Hard welds better (excellent vs very good).
347-1/2 HardChoose it when strength drives the design.
347-1/4 HardChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
347-1/2 Hard vs 347-1/4 Hard: 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
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 · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Same in both: Density 7.96 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,425°C2,597 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 16 W/m·K9.2 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 16.6 µm/m·K9.2 µin/in·°F · Latent Heat of Fusion 280 J/g120 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 7.4×10⁻⁷ Ω·m29.1 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.08 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 80 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 57 MJ/kg24,506 BTU/lb · Embodied Carbon (primary production) 5.5 kg CO₂/kg · Embodied Water 140 L/kg16.8 gal/lb · Typical Recycled Content 60%
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.
347-1/2 Hard vs 347-1/4 Hard — frequently asked
Is 347-1/2 Hard stronger than 347-1/4 Hard?
Yes. 347-1/2 Hard has a typical yield strength of 790 MPa (115 ksi) against 550 MPa (79.8 ksi) for 347-1/4 Hard — about 44% more. Tensile strength is 1,035 MPa (150 ksi) vs 900 MPa (131 ksi).
Which condition does FabDigit quote by default, 1/2 Hard or 1/4 Hard?
Solution Annealed is the default 347 condition in the FabDigit quote flow (neither 1/2 Hard nor 1/4 Hard). 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, 347-1/2 Hard or 347-1/4 Hard?
347-1/4 Hard, by a small margin. Both rate fair for machinability — 40/100 against 35/100 for 347-1/2 Hard; for welding the order is 347-1/4 Hard first (excellent, 85/100) then 347-1/2 Hard (very good, 75/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 347-1/2 Hard and 347-1/4 Hard 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.