Aluminum ZL203-T4 vs ZL203-T7
Aluminum · ZL203 temper comparison
ZL203-T4 and ZL203-T7 are two conditions of the same aluminum grade, ZL203: 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. ZL203-T7 is the stronger of the two: yield strength 150 MPa (21.8 ksi) against 110 MPa (16 ksi) for ZL203-T4, about 36% more. In exchange, ZL203-T4 is the more ductile: elongation 8% versus 3% for ZL203-T7, and ZL203-T7 is harder (68 HB vs 60 HB). ZL203-T7 runs hotter in service (175°C vs 120°C continuous) and ZL203-T7 conducts heat better (155 W/m·K vs 138 W/m·K).
ZL203-T4Choose it when the part is bent, formed or impact-loaded.
ZL203-T7Choose it when strength drives the design, or when the part sees heat.
ZL203-T4 vs ZL203-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
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 70 GPa10.2 Msi · Shear Modulus 26 GPa3.8 Msi · Bulk Modulus 69 GPa10 Msi · Poisson's Ratio 0.33
Physical
Density and transition temperatures.
Same in both: Density 2.8 g/cm³0.1 lb/in³ · Melting Point (Solidus) 545°C1,013 °F · Liquidus Temperature 635°C1,175 °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 963 J/kg·K0.23 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 23 µm/m·K12.8 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
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.7 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Formability (cold)
Same in both: Machinability 80 / 100 · Machinability Rating (AISI 1212 = 100 %) 190% · Weldability 25 / 100 · Castability 45 / 100 · Brazeability / Solderability 20 / 100 · Polishability 45 / 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 25%
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.
ZL203-T4 vs ZL203-T7 — frequently asked
Is ZL203-T7 stronger than ZL203-T4?
Yes. ZL203-T7 has a typical yield strength of 150 MPa (21.8 ksi) against 110 MPa (16 ksi) for ZL203-T4 — about 36% more. Tensile strength is 200 MPa (29 ksi) vs 215 MPa (31.2 ksi).
Which condition does FabDigit quote by default, T4 or T7?
T4 is the default ZL203 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 ZL203-T4 over ZL203-T7?
Pick ZL203-T4 when the part is bent, formed or impact-loaded. Pick ZL203-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 ZL203-T4 and ZL203-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.