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Aluminum AC4C-T6 vs AC4C-T7

Aluminum · AC4C temper comparison

AC4C-T6 and AC4C-T7 are two conditions of the same aluminum grade, AC4C: T6 (solution heat treated and artificially aged) versus T7 (solution heat treated and overaged (stabilized)). The chemistry is identical, so every difference below comes from the condition. AC4C-T7 is the stronger of the two: yield strength 195 MPa (28.3 ksi) against 180 MPa (26.1 ksi) for AC4C-T6, about 8% more. AC4C-T6 is harder — 80 HB against 70 HB for AC4C-T7 — which matters for wear surfaces and threads. AC4C-T7 runs hotter in service (200°C vs 150°C continuous).

AC4C-T6Choose it when surface hardness matters.

AC4C-T7Choose it when strength drives the design, or when the part sees heat.

AC4C-T6 vs AC4C-T7: properties

AC4C-T6AC4C-T7

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

250 MPa36.3 ksi
230 MPa33.4 ksi

Yield Strength (0.2% offset)

180 MPa26.1 ksi
195 MPa28.3 ksi

Compressive Strength

185 MPa26.8 ksi
200 MPa29 ksi

Shear Strength

180 MPa26.1 ksi
160 MPa23.2 ksi

Fatigue Strength (Endurance Limit)

90 MPa13.1 ksi
80 MPa11.6 ksi

Fracture Toughness (K_IC)

20 MPa·√m18.2 ksi·√in
23 MPa·√m20.9 ksi·√in

Charpy V-Notch Impact (RT)

5 J3.7 ft·lbf
6 J4.4 ft·lbf

Hardness, Brinell

80 HB
70 HB

Hardness, Vickers

85 HV
75 HV

Same in both: Elastic (Young's) Modulus 72.4 GPa10.5 Msi · Shear Modulus 27 GPa3.9 Msi · Bulk Modulus 71 GPa10.3 Msi · Poisson's Ratio 0.33 · Elongation at Break 5%

Physical

Density and transition temperatures.

Same in both: Density 2.68 g/cm³0.1 lb/in³ · Melting Point (Solidus) 557°C1,035 °F · Liquidus Temperature 613°C1,135 °F

Thermal

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

Thermal Conductivity

151 W/m·K87.2 BTU/hr·ft·°F
156 W/m·K90.1 BTU/hr·ft·°F

Max Service Temperature (continuous)

150°C302 °F
200°C392 °F

Same in both: Specific Heat Capacity 963 J/kg·K0.23 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 21.5 µm/m·K11.9 µin/in·°F · Latent Heat of Fusion 389 J/g167 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

39 % IACS
42 % IACS

Electrical Resistivity

4.4×10⁻⁸ Ω·m1.73 µΩ·in
4.1×10⁻⁸ Ω·m1.61 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

58 / 100
61 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V

Manufacturability

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

Machinability

62 / 100
60 / 100

Weldability

75 / 100
78 / 100

Formability (cold)

12 / 100
14 / 100

Same in both: Castability 93 / 100 · Brazeability / Solderability 30 / 100 · Polishability 50 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 175 MJ/kg75,237 BTU/lb · Embodied Carbon (primary production) 11.5 kg CO₂/kg · Embodied Water 1,200 L/kg144 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 scaleAC4C

AC4C-T6 vs AC4C-T7 — frequently asked

Is AC4C-T7 stronger than AC4C-T6?

Yes. AC4C-T7 has a typical yield strength of 195 MPa (28.3 ksi) against 180 MPa (26.1 ksi) for AC4C-T6 — about 8% more. Tensile strength is 230 MPa (33.4 ksi) vs 250 MPa (36.3 ksi).

Which condition does FabDigit quote by default, T6 or T7?

T6 is the default AC4C 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 AC4C-T6 over AC4C-T7?

Pick AC4C-T6 when surface hardness matters. Pick AC4C-T7 when strength drives the design, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AC4C-T6 and AC4C-T7 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.