Stainless Steel CA40-A vs CA40 H+T 650
Stainless Steel · CA40 temper comparison
CA40-A and CA40 H+T 650 are two conditions of the same stainless steel grade, CA40: A (solution annealed) versus H+T 650 (austenitized 980–1010 °C, air/oil quenched, tempered 620–675 °C). The chemistry is identical, so every difference below comes from the condition. CA40 H+T 650 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 415 MPa (60.2 ksi) for CA40-A, about 49% more; tensile strength follows at 795 MPa (115 ksi) vs 640 MPa (92.8 ksi). In exchange, CA40-A is the more ductile: elongation 24% versus 18% for CA40 H+T 650, and CA40 H+T 650 is harder (250 HB vs 200 HB). CA40 H+T 650 runs hotter in service (550°C vs 500°C continuous). On the shop floor, CA40-A machines more easily (50 vs 40 out of 100).
CA40-AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
CA40 H+T 650Choose it when strength drives the design, or when the part sees heat.
CA40-A vs CA40 H+T 650: 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, 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 · Compressive Strength 650 MPa94.3 ksi · Shear Strength 490 MPa71.1 ksi · Fracture Toughness (K_IC) 60 MPa·√m54.6 ksi·√in · Hardness, Rockwell C 24 HRC
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 1,520°C2,768 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 24.2 W/m·K14 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.4 µm/m·K5.8 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -20°C-4 °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) -0.32 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 28 / 100 · Formability (cold) 8 / 100 · Castability 72 / 100 · Brazeability / Solderability 50 / 100 · Polishability 72 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 40 MJ/kg17,197 BTU/lb · Embodied Carbon (primary production) 2.9 kg CO₂/kg · Embodied Water 90 L/kg10.8 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.
CA40-A vs CA40 H+T 650 — frequently asked
Is CA40 H+T 650 stronger than CA40-A?
Yes. CA40 H+T 650 has a typical yield strength of 620 MPa (89.9 ksi) against 415 MPa (60.2 ksi) for CA40-A — about 49% more. Tensile strength is 795 MPa (115 ksi) vs 640 MPa (92.8 ksi).
Which condition does FabDigit quote by default, A or H+T 650?
H+T 650 is the default CA40 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, CA40-A or CA40 H+T 650?
CA40-A, by a small margin. Both rate fair for machinability — 50/100 against 40/100 for CA40 H+T 650.
Ready to make it?
Upload a CAD file and FabDigit prices the part in CA40-A and CA40 H+T 650 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.