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Magnesium Alloy AZ91D Powder-T4 vs AZ91D Powder-T6

Magnesium Alloy · AZ91D Powder temper comparison

AZ91D Powder-T4 and AZ91D Powder-T6 are two conditions of the same magnesium alloy grade, AZ91D Powder: T4 (solution heat treated and naturally aged) versus T6 (solution heat treated and artificially aged). The chemistry is identical, so every difference below comes from the condition. AZ91D Powder-T6 is the stronger of the two: yield strength 160 MPa (23.2 ksi) against 105 MPa (15.2 ksi) for AZ91D Powder-T4, about 52% more; tensile strength follows at 285 MPa (41.3 ksi) vs 265 MPa (38.4 ksi). In exchange, AZ91D Powder-T4 is the more ductile: elongation 10% versus 5% for AZ91D Powder-T6, and AZ91D Powder-T6 is harder (72 HB vs 55 HB). AZ91D Powder-T6 conducts heat better (53 W/m·K vs 46 W/m·K). On the shop floor, AZ91D Powder-T4 welds better (65 vs 55 out of 100).

AZ91D Powder-T4Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

AZ91D Powder-T6Choose it when strength drives the design.

AZ91D Powder-T4 vs AZ91D Powder-T6: properties

AZ91D Powder-T4AZ91D Powder-T6

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

265 MPa38.4 ksi
285 MPa41.3 ksi

Yield Strength (0.2% offset)

105 MPa15.2 ksi
160 MPa23.2 ksi

Elongation at Break

10%
5%

Compressive Strength

300 MPa43.5 ksi
345 MPa50 ksi

Shear Strength

125 MPa18.1 ksi
140 MPa20.3 ksi

Fatigue Strength (Endurance Limit)

70 MPa10.2 ksi
80 MPa11.6 ksi

Fracture Toughness (K_IC)

17 MPa·√m15.5 ksi·√in
12 MPa·√m10.9 ksi·√in

Charpy V-Notch Impact (RT)

5 J3.7 ft·lbf
2 J1.1 ft·lbf

Hardness, Brinell

55 HB
72 HB

Hardness, Vickers

65 HV
85 HV

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

46 W/m·K26.6 BTU/hr·ft·°F
53 W/m·K30.6 BTU/hr·ft·°F

Max Service Temperature (continuous)

120°C248 °F
130°C266 °F

Same in both: Specific Heat Capacity 1,020 J/kg·K0.24 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 -50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10.5 % IACS
12.5 % IACS

Electrical Resistivity

1.64×10⁻⁷ Ω·m6.46 µΩ·in
1.38×10⁻⁷ Ω·m5.43 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

28 / 100
24 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -1.55 V

Manufacturability

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

Weldability

65 / 100
55 / 100

Formability (cold)

30 / 100
12 / 100

Same in both: Machinability 95 / 100 · Castability 92 / 100 · Brazeability / Solderability 15 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 375 MJ/kg161,221 BTU/lb · Embodied Carbon (primary production) 32 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb · Typical Recycled Content 5%

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.

701001502001.41.51.61.71.8Density (g/cm³)Yield strength (MPa) — log scaleAZ91D Powder

AZ91D Powder-T4 vs AZ91D Powder-T6 — frequently asked

Is AZ91D Powder-T6 stronger than AZ91D Powder-T4?

Yes. AZ91D Powder-T6 has a typical yield strength of 160 MPa (23.2 ksi) against 105 MPa (15.2 ksi) for AZ91D Powder-T4 — about 52% more. Tensile strength is 285 MPa (41.3 ksi) vs 265 MPa (38.4 ksi).

Which condition does FabDigit quote by default, T4 or T6?

AB is the default AZ91D Powder condition in the FabDigit quote flow (neither T4 nor T6). 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 welds better, AZ91D Powder-T4 or AZ91D Powder-T6?

AZ91D Powder-T4. Its weldability rates good (65/100) against good (55/100) for AZ91D Powder-T6.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AZ91D Powder-T4 and AZ91D Powder-T6 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.