Stainless Steel 302-1/4 Hard vs 302-3/4 Hard
Stainless Steel · 302 temper comparison
302 1_4_hard and 302-3/4 Hard are two conditions of the same stainless steel grade, 302: 1_4_hard versus 3/4 Hard (three-quarter hard). The chemistry is identical, so every difference below comes from the condition. 302-3/4 Hard is the stronger of the two: yield strength 965 MPa (140 ksi) against 585 MPa (84.8 ksi) for 302 1_4_hard, about 65% more; tensile strength follows at 1,240 MPa (180 ksi) vs 900 MPa (131 ksi). In exchange, 302 1_4_hard is the more ductile: elongation 15% versus 5% for 302-3/4 Hard, and 302-3/4 Hard is harder (350 HB vs 260 HB). On the shop floor, 302 1_4_hard welds better (good vs fair).
302 1_4_hardChoose it when the part is bent, formed or impact-loaded, or when it will be welded.
302-3/4 HardChoose it when strength drives the design.
302 1_4_hard vs 302-3/4 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.
Elastic (Young's) Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
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: Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 152 GPa22 Msi · Reduction in Area 40%
Physical
Density and transition temperatures.
Same in both: Density 7.9 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,420°C2,588 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 300°C572 °F · 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) -0.08 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Polishability
Same in both: Brazeability / Solderability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 5.2 kg CO₂/kg · Embodied Water 110 L/kg13.2 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.
302 1_4_hard vs 302-3/4 Hard — frequently asked
Is 302-3/4 Hard stronger than 302 1_4_hard?
Yes. 302-3/4 Hard has a typical yield strength of 965 MPa (140 ksi) against 585 MPa (84.8 ksi) for 302 1_4_hard — about 65% more. Tensile strength is 1,240 MPa (180 ksi) vs 900 MPa (131 ksi).
Which condition does FabDigit quote by default, 1_4_hard or 3/4 Hard?
Annealed is the default 302 condition in the FabDigit quote flow (neither 1_4_hard nor 3/4 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, 302 1_4_hard or 302-3/4 Hard?
302 1_4_hard, by a small margin. Both rate fair for machinability — 45/100 against 38/100 for 302-3/4 Hard; for welding the order is 302 1_4_hard first (good, 60/100) then 302-3/4 Hard (fair, 40/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 302 1_4_hard and 302-3/4 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.