Magnesium Alloy AZ91C-F vs AZ91C-T4
Magnesium Alloy · AZ91C temper comparison
AZ91C-F and AZ91C-T4 are two conditions of the same magnesium alloy grade, AZ91C: F (as fabricated) versus T4 (solution heat treated and naturally aged). The chemistry is identical, so every difference below comes from the condition. AZ91C-F is the stronger of the two: yield strength 97 MPa (14.1 ksi) against 90 MPa (13.1 ksi) for AZ91C-T4, about 8% more. In exchange, AZ91C-T4 is the more ductile: elongation 14% versus 2.5% for AZ91C-F, and AZ91C-F is harder (60 HB vs 55 HB). AZ91C-F runs hotter in service (120°C vs 110°C continuous).
AZ91C-FChoose it when strength drives the design, or when the part sees heat.
AZ91C-T4Choose it when the part is bent, formed or impact-loaded.
AZ91C-F vs AZ91C-T4: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all magnesium alloy 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 magnesium alloy 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)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 45 GPa6.5 Msi · Shear Modulus 17 GPa2.5 Msi · Bulk Modulus 45 GPa6.5 Msi · Poisson's Ratio 0.35
Physical
Density and transition temperatures.
Same in both: Density 1.81 g/cm³0.07 lb/in³ · Melting Point (Solidus) 470°C878 °F · Liquidus Temperature 595°C1,103 °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 1,050 J/kg·K0.25 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 26 µm/m·K14.4 µin/in·°F · Latent Heat of Fusion 373 J/g160 BTU/lb · Min Service Temperature -100°C-148 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 12 % IACS · Electrical Resistivity 1.41×10⁻⁷ Ω·m5.55 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -1.55 V · Corrosion Resistance 20 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 480% · Weldability 70 / 100 · Formability (cold) 12 / 100 · Castability 85 / 100 · Brazeability / Solderability 20 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 355 MJ/kg152,623 BTU/lb · Embodied Carbon (primary production) 28 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb · Typical Recycled Content 35%
Strength versus weight
Yield strength against density for every magnesium alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
AZ91C-F vs AZ91C-T4 — frequently asked
Is AZ91C-F stronger than AZ91C-T4?
Yes. AZ91C-F has a typical yield strength of 97 MPa (14.1 ksi) against 90 MPa (13.1 ksi) for AZ91C-T4 — about 8% more. Tensile strength is 165 MPa (23.9 ksi) vs 275 MPa (39.9 ksi).
Which condition does FabDigit quote by default, F or T4?
F is the default AZ91C 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 AZ91C-F over AZ91C-T4?
Pick AZ91C-F when strength drives the design, or when the part sees heat. Pick AZ91C-T4 when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in AZ91C-F and AZ91C-T4 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.