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Magnesium Alloy AZ61A vs AZ91D Powder

Magnesium Alloy · grade comparison

Magnesium Alloy AZ61A and AZ91D Powder are both magnesium alloy grades. AZ91D Powder is the stronger of the two: yield strength 245 MPa (35.5 ksi) against 230 MPa (33.4 ksi) for AZ61A, about 7% more. In exchange, AZ61A is the more ductile: elongation 16% versus 2.5% for AZ91D Powder, and AZ91D Powder is harder (75 HB vs 60 HB). AZ61A conducts heat better (80 W/m·K vs 51 W/m·K). On the shop floor, AZ61A welds better (very good vs good) and AZ61A sits in a lower cost tier (standard, $$) than AZ91D Powder (high, $$$$).

AZ61AChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

AZ91D PowderChoose it when strength drives the design.

AZ61A vs AZ91D Powder: properties

AZ61AAZ91D Powder

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

310 MPa45 ksi
290 MPa42.1 ksi

Yield Strength (0.2% offset)

230 MPa33.4 ksi
245 MPa35.5 ksi

Elongation at Break

16%
2.5%

Compressive Strength

130 MPa18.9 ksi
330 MPa47.9 ksi

Shear Strength

140 MPa20.3 ksi
145 MPa21 ksi

Fatigue Strength (Endurance Limit)

125 MPa18.1 ksi
70 MPa10.2 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 J1.5 ft·lbf

Hardness, Brinell

60 HB
75 HB

Hardness, Vickers

—
90 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.

Density

1.8 g/cm³0.07 lb/in³
1.81 g/cm³0.07 lb/in³

Melting Point (Solidus)

510°C950 °F
470°C878 °F

Liquidus Temperature

620°C1,148 °F
595°C1,103 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

80 W/m·K46.2 BTU/hr·ft·°F
51 W/m·K29.5 BTU/hr·ft·°F

Specific Heat Capacity

1,040 J/kg·K0.25 BTU/lb·°F
1,020 J/kg·K0.24 BTU/lb·°F

Max Service Temperature (continuous)

130°C266 °F
120°C248 °F

Min Service Temperature

-60°C-76 °F
-50°C-58 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 26 µm/m·K14.4 µin/in·°F · Latent Heat of Fusion 373 J/g160 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

13.5 % IACS
12 % IACS

Electrical Resistivity

1.25×10⁻⁷ Ω·m4.92 µΩ·in
1.41×10⁻⁷ Ω·m5.55 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

18 / 100
25 / 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.

Machinability Rating (AISI 1212 = 100 %)

500%
—

Weldability

70 / 100
60 / 100

Formability (cold)

25 / 100
15 / 100

Castability

40 / 100
92 / 100

Brazeability / Solderability

20 / 100
15 / 100

Polishability

60 / 100
55 / 100

Same in both: Machinability 95 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

340 MJ/kg146,174 BTU/lb
375 MJ/kg161,221 BTU/lb

Embodied Carbon (primary production)

27 kg CO₂/kg
32 kg CO₂/kg

Typical Recycled Content

25%
5%

Same in both: Embodied Water 500 L/kg59.9 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

172 kN·m/kg
160 kN·m/kg

Specific Stiffness (E / density)

25 MN·m/kg
24.9 MN·m/kg

Modulus of Resilience

588 kJ/m³
667 kJ/m³

Thermal Diffusivity

42.7 mm²/s
27.6 mm²/s

Thermal Shock Resistance Index

21
13

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 scaleAZ61AAZ91D Powder

Manufacturing and finishing

CapabilityAZ61AAZ91D Powder
CNC machiningYes—
Sheet metalYes—
Default conditionF—
Relative cost$$ Standard$$$$ High
Min. machined wall0.8 mm—
Best machined surfaceRa 0.8 µm—
Anodizing Type IIYes—
Chem Film (Alodine)Yes—
E-CoatingYes—
Hard Anodize Type III w/ PTFEYes—
Hard Anodizing Type IIIYes—
PaintingYes—
Powder CoatingYes—

AZ61A vs AZ91D Powder — frequently asked

Is AZ91D Powder stronger than AZ61A?

Yes. AZ91D Powder has a typical yield strength of 245 MPa (35.5 ksi) against 230 MPa (33.4 ksi) for AZ61A — about 7% more. Tensile strength is 290 MPa (42.1 ksi) vs 310 MPa (45 ksi).

Which is cheaper, AZ61A or AZ91D Powder?

AZ61A is the lower-cost material: it sits in the standard tier ($$) while AZ91D Powder is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, AZ61A or AZ91D Powder?

AZ61A. Its weldability rates very good (70/100) against good (60/100) for AZ91D Powder.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AZ61A and AZ91D Powder 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.