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Aluminum AC9B-T5 vs AC9B-T6

Aluminum · AC9B temper comparison

AC9B-T5 and AC9B-T6 are two conditions of the same aluminum grade, AC9B: T5 (cooled from hot working and artificially aged) versus T6 (solution heat treated and artificially aged). The chemistry is identical, so every difference below comes from the condition. AC9B-T6 is the stronger of the two: yield strength 200 MPa (29 ksi) against 175 MPa (25.4 ksi) for AC9B-T5, about 14% more; tensile strength follows at 220 MPa (31.9 ksi) vs 190 MPa (27.6 ksi). AC9B-T6 is harder — 140 HB against 115 HB for AC9B-T5 — which matters for wear surfaces and threads. AC9B-T6 runs hotter in service (250°C vs 230°C continuous).

AC9B-T6Choose it when strength drives the design, or when surface hardness matters.

AC9B-T5 vs AC9B-T6: properties

AC9B-T5AC9B-T6

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

190 MPa27.6 ksi
220 MPa31.9 ksi

Yield Strength (0.2% offset)

175 MPa25.4 ksi
200 MPa29 ksi

Compressive Strength

400 MPa58 ksi
450 MPa65.3 ksi

Shear Strength

133 MPa19.3 ksi
155 MPa22.5 ksi

Fatigue Strength (Endurance Limit)

85 MPa12.3 ksi
90 MPa13.1 ksi

Charpy V-Notch Impact (RT)

1 J1 ft·lbf
2 J1.1 ft·lbf

Hardness, Brinell

115 HB
140 HB

Same in both: Elastic (Young's) Modulus 82 GPa11.9 Msi · Shear Modulus 31 GPa4.5 Msi · Bulk Modulus 76 GPa11 Msi · Poisson's Ratio 0.33 · Elongation at Break 0.5% · Fracture Toughness (K_IC) 15 MPa·√m13.7 ksi·√in

Physical

Density and transition temperatures.

Same in both: Density 2.68 g/cm³0.1 lb/in³ · Melting Point (Solidus) 507°C945 °F · Liquidus Temperature 670°C1,238 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

135 W/m·K78 BTU/hr·ft·°F
130 W/m·K75.1 BTU/hr·ft·°F

Max Service Temperature (continuous)

230°C446 °F
250°C482 °F

Same in both: Specific Heat Capacity 880 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 17.8 µm/m·K9.9 µin/in·°F · Latent Heat of Fusion 425 J/g183 BTU/lb · Min Service Temperature -80°C-112 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

26 % IACS
25 % IACS

Electrical Resistivity

6.6×10⁻⁸ Ω·m2.6 µΩ·in
6.9×10⁻⁸ Ω·m2.72 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.8 V · Corrosion Resistance 48 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

29 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

41%
40%

Same in both: Weldability 22 / 100 · Formability (cold) 3 / 100 · Castability 70 / 100 · Brazeability / Solderability 20 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 155 MJ/kg66,638 BTU/lb · Embodied Carbon (primary production) 10.5 kg CO₂/kg · Embodied Water 1,100 L/kg132 gal/lb · Typical Recycled Content 55%

Strength versus weight

Yield strength against density for every aluminum grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

20501002005002.22.42.62.83Density (g/cm³)Yield strength (MPa) — log scaleAC9B

AC9B-T5 vs AC9B-T6 — frequently asked

Is AC9B-T6 stronger than AC9B-T5?

Yes. AC9B-T6 has a typical yield strength of 200 MPa (29 ksi) against 175 MPa (25.4 ksi) for AC9B-T5 — about 14% more. Tensile strength is 220 MPa (31.9 ksi) vs 190 MPa (27.6 ksi).

Which condition does FabDigit quote by default, T5 or T6?

T6 is the default AC9B 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.

When should I choose AC9B-T5 over AC9B-T6?

Pick AC9B-T6 when strength drives the design, or when surface hardness matters.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AC9B-T5 and AC9B-T6 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.