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Aluminum AC4CH-T4 vs AC4CH-T5

Aluminum · AC4CH temper comparison

AC4CH-T4 and AC4CH-T5 are two conditions of the same aluminum grade, AC4CH: T4 (solution heat treated and naturally aged) versus T5 (cooled from hot working and artificially aged). The chemistry is identical, so every difference below comes from the condition. AC4CH-T5 is the stronger of the two: yield strength 145 MPa (21 ksi) against 120 MPa (17.4 ksi) for AC4CH-T4, about 21% more. In exchange, AC4CH-T4 is the more ductile: elongation 12% versus 4% for AC4CH-T5, and AC4CH-T5 is harder (65 HB vs 60 HB). AC4CH-T5 runs hotter in service (150°C vs 120°C continuous).

AC4CH-T4Choose it when the part is bent, formed or impact-loaded.

AC4CH-T5Choose it when strength drives the design, or when the part sees heat.

AC4CH-T4 vs AC4CH-T5: properties

AC4CH-T4AC4CH-T5

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

230 MPa33.4 ksi
200 MPa29 ksi

Yield Strength (0.2% offset)

120 MPa17.4 ksi
145 MPa21 ksi

Elongation at Break

12%
4%

Compressive Strength

125 MPa18.1 ksi
215 MPa31.2 ksi

Shear Strength

170 MPa24.7 ksi
150 MPa21.8 ksi

Fatigue Strength (Endurance Limit)

70 MPa10.2 ksi
75 MPa10.9 ksi

Fracture Toughness (K_IC)

32 MPa·√m29.1 ksi·√in
25 MPa·√m22.8 ksi·√in

Charpy V-Notch Impact (RT)

8 J5.9 ft·lbf
4 J3 ft·lbf

Hardness, Brinell

60 HB
65 HB

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

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

148 W/m·K85.5 BTU/hr·ft·°F
155 W/m·K89.6 BTU/hr·ft·°F

Max Service Temperature (continuous)

120°C248 °F
150°C302 °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

38 % IACS
41 % IACS

Electrical Resistivity

4.54×10⁻⁸ Ω·m1.79 µΩ·in
4.4×10⁻⁸ Ω·m1.73 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

57 / 100
55 / 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 Rating (AISI 1212 = 100 %)

60%
70%

Formability (cold)

22 / 100
15 / 100

Same in both: Machinability 55 / 100 · Weldability 75 / 100 · Castability 92 / 100 · Brazeability / Solderability 30 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,100 L/kg132 gal/lb · Typical Recycled Content 20%

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 scaleAC4CH

AC4CH-T4 vs AC4CH-T5 — frequently asked

Is AC4CH-T5 stronger than AC4CH-T4?

Yes. AC4CH-T5 has a typical yield strength of 145 MPa (21 ksi) against 120 MPa (17.4 ksi) for AC4CH-T4 — about 21% more. Tensile strength is 200 MPa (29 ksi) vs 230 MPa (33.4 ksi).

Which condition does FabDigit quote by default, T4 or T5?

T6 is the default AC4CH condition in the FabDigit quote flow (neither T4 nor T5). 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 AC4CH-T4 over AC4CH-T5?

Pick AC4CH-T4 when the part is bent, formed or impact-loaded. Pick AC4CH-T5 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 AC4CH-T4 and AC4CH-T5 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.