Aluminum ZL201-T4 vs ZL201-T7
Aluminum · ZL201 temper comparison
ZL201-T4 and ZL201-T7 are two conditions of the same aluminum grade, ZL201: T4 (solution heat treated and naturally aged) versus T7 (solution heat treated and overaged (stabilized)). The chemistry is identical, so every difference below comes from the condition. ZL201-T7 is the stronger of the two: yield strength 265 MPa (38.4 ksi) against 185 MPa (26.8 ksi) for ZL201-T4, about 43% more. In exchange, ZL201-T4 is the more ductile: elongation 10% versus 3% for ZL201-T7, and ZL201-T7 is harder (82 HB vs 72 HB). ZL201-T7 runs hotter in service (250°C vs 120°C continuous) and ZL201-T7 conducts heat better (140 W/m·K vs 122 W/m·K).
ZL201-T4Choose it when the part is bent, formed or impact-loaded.
ZL201-T7Choose it when strength drives the design, or when the part sees heat.
ZL201-T4 vs ZL201-T7: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum 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 aluminum 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
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 70 GPa10.2 Msi · Shear Modulus 26 GPa3.8 Msi · Bulk Modulus 71 GPa10.3 Msi · Poisson's Ratio 0.33 · Compressive Strength 270 MPa39.2 ksi
Physical
Density and transition temperatures.
Same in both: Density 2.83 g/cm³0.1 lb/in³ · Melting Point (Solidus) 545°C1,013 °F · Liquidus Temperature 650°C1,202 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 880 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 22.5 µm/m·K12.5 µin/in·°F · Latent Heat of Fusion 390 J/g168 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 5.2×10⁻⁸ Ω·m2.05 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.68 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 300% · Weldability 25 / 100 · Formability (cold) 10 / 100 · Castability 35 / 100 · Brazeability / Solderability 15 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 195 MJ/kg83,835 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,150 L/kg138 gal/lb · Typical Recycled Content 15%
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.
ZL201-T4 vs ZL201-T7 — frequently asked
Is ZL201-T7 stronger than ZL201-T4?
Yes. ZL201-T7 has a typical yield strength of 265 MPa (38.4 ksi) against 185 MPa (26.8 ksi) for ZL201-T4 — about 43% more. Tensile strength is 330 MPa (47.9 ksi) vs 320 MPa (46.4 ksi).
Which condition does FabDigit quote by default, T4 or T7?
T5 is the default ZL201 condition in the FabDigit quote flow (neither T4 nor T7). 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, ZL201-T4 or ZL201-T7?
ZL201-T7, by a small margin. Both rate very good for machinability — 75/100 against 70/100 for ZL201-T4.
Ready to make it?
Upload a CAD file and FabDigit prices the part in ZL201-T4 and ZL201-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.