Stainless Steel CA15-QT315 vs CA15-QT595
Stainless Steel · CA15 temper comparison
CA15-QT315 and CA15-QT595 are two conditions of the same stainless steel grade, CA15: QT315 (Q&T) versus QT595 (Q&T). The chemistry is identical, so every difference below comes from the condition. CA15-QT315 is the stronger of the two: yield strength 900 MPa (131 ksi) against 690 MPa (100 ksi) for CA15-QT595, about 30% more; tensile strength follows at 1,100 MPa (160 ksi) vs 830 MPa (120 ksi). In exchange, CA15-QT595 is the more ductile: elongation 18% versus 11% for CA15-QT315, and CA15-QT315 is harder (350 HB vs 260 HB). CA15-QT595 runs hotter in service (540°C vs 250°C continuous). On the shop floor, CA15-QT595 machines more easily (fair vs poor).
CA15-QT315Choose it when strength drives the design.
CA15-QT595Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
CA15-QT315 vs CA15-QT595: 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
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 78 GPa11.3 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.28 · Shear Strength 430 MPa62.4 ksi · Fracture Toughness (K_IC) 85 MPa·√m77.4 ksi·√in
Physical
Density and transition temperatures.
Same in both: Density 7.61 g/cm³0.27 lb/in³ · Melting Point (Solidus) 1,480°C2,696 °F · Liquidus Temperature 1,530°C2,786 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 24.5 W/m·K14.2 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.3 µm/m·K5.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -29°C-20 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3 % IACS · Electrical Resistivity 5.7×10⁻⁷ Ω·m22.4 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.3 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Same in both: Weldability 40 / 100 · Formability (cold) 10 / 100 · Castability 70 / 100 · Brazeability / Solderability 40 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 40 MJ/kg17,197 BTU/lb · Embodied Carbon (primary production) 3.6 kg CO₂/kg · Embodied Water 180 L/kg21.6 gal/lb · Typical Recycled Content 75%
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.
CA15-QT315 vs CA15-QT595 — frequently asked
Is CA15-QT315 stronger than CA15-QT595?
Yes. CA15-QT315 has a typical yield strength of 900 MPa (131 ksi) against 690 MPa (100 ksi) for CA15-QT595 — about 30% more. Tensile strength is 1,100 MPa (160 ksi) vs 830 MPa (120 ksi).
Which condition does FabDigit quote by default, QT315 or QT595?
NT650 is the default CA15 condition in the FabDigit quote flow (neither QT315 nor QT595). 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, CA15-QT315 or CA15-QT595?
CA15-QT595. Its machinability rates fair (38/100) against poor (25/100) for CA15-QT315.
Ready to make it?
Upload a CAD file and FabDigit prices the part in CA15-QT315 and CA15-QT595 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.