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Stainless Steel CA40-A vs CA40 H+T 540

Stainless Steel · CA40 temper comparison

CA40-A and CA40 H+T 540 are two conditions of the same stainless steel grade, CA40: A (solution annealed) versus H+T 540 (quenched, tempered 480–590 °C). The chemistry is identical, so every difference below comes from the condition. CA40 H+T 540 is the stronger of the two: yield strength 790 MPa (115 ksi) against 415 MPa (60.2 ksi) for CA40-A, about 90% more; tensile strength follows at 1,000 MPa (145 ksi) vs 640 MPa (92.8 ksi). In exchange, CA40-A is the more ductile: elongation 24% versus 13% for CA40 H+T 540, and CA40 H+T 540 is harder (310 HB vs 200 HB). CA40-A runs hotter in service (500°C vs 450°C continuous). On the shop floor, CA40-A machines more easily (fair vs poor).

CA40-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

CA40 H+T 540Choose it when strength drives the design.

CA40-A vs CA40 H+T 540: properties

CA40-ACA40 H+T 540

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

640 MPa92.8 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
790 MPa115 ksi

Elongation at Break

24%
13%

Reduction in Area

55%
35%

Fatigue Strength (Endurance Limit)

290 MPa42.1 ksi
420 MPa60.9 ksi

Fracture Toughness (K_IC)

60 MPa·√m54.6 ksi·√in
45 MPa·√m41 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
12 J8.9 ft·lbf

Hardness, Brinell

200 HB
310 HB

Hardness, Rockwell C

24 HRC
33 HRC

Hardness, Vickers

210 HV
325 HV

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

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)

500°C932 °F
450°C842 °F

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

32 / 100
33 / 100

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

50 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
28%

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.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scaleCA40

CA40-A vs CA40 H+T 540 — frequently asked

Is CA40 H+T 540 stronger than CA40-A?

Yes. CA40 H+T 540 has a typical yield strength of 790 MPa (115 ksi) against 415 MPa (60.2 ksi) for CA40-A — about 90% more. Tensile strength is 1,000 MPa (145 ksi) vs 640 MPa (92.8 ksi).

Which condition does FabDigit quote by default, A or H+T 540?

H+T 650 is the default CA40 condition in the FabDigit quote flow (neither A nor H+T 540). 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 540?

CA40-A. Its machinability rates fair (50/100) against poor (30/100) for CA40 H+T 540.

Ready to make it?

Upload a CAD file and FabDigit prices the part in CA40-A and CA40 H+T 540 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.