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Magnesium Alloy AZ61B vs ZK60A

Magnesium Alloy · grade comparison

Magnesium Alloy AZ61B and ZK60A are both magnesium alloy grades. ZK60A is the stronger of the two: yield strength 260 MPa (37.7 ksi) against 230 MPa (33.4 ksi) for AZ61B, about 13% more; tensile strength follows at 340 MPa (49.3 ksi) vs 310 MPa (45 ksi). In exchange, AZ61B is the more ductile: elongation 16% versus 14% for ZK60A, and ZK60A is harder (75 HB vs 60 HB). ZK60A runs hotter in service (150°C vs 120°C continuous) and ZK60A conducts heat better (121 W/m·K vs 80 W/m·K). On the shop floor, AZ61B welds better (very good vs poor).

AZ61BChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

ZK60AChoose it when strength drives the design, or when the part sees heat.

AZ61B vs ZK60A: properties

AZ61BZK60A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

17 GPa2.5 Msi
16.5 GPa2.4 Msi

Tensile Strength (Ultimate)

310 MPa45 ksi
340 MPa49.3 ksi

Yield Strength (0.2% offset)

230 MPa33.4 ksi
260 MPa37.7 ksi

Elongation at Break

16%
14%

Compressive Strength

130 MPa18.9 ksi
215 MPa31.2 ksi

Shear Strength

140 MPa20.3 ksi
165 MPa23.9 ksi

Fatigue Strength (Endurance Limit)

145 MPa21 ksi
130 MPa18.9 ksi

Fracture Toughness (K_IC)

20 MPa·√m18.2 ksi·√in
14 MPa·√m12.7 ksi·√in

Charpy V-Notch Impact (RT)

5 J3.7 ft·lbf
6 J4.4 ft·lbf

Hardness, Brinell

60 HB
75 HB

Hardness, Vickers

—
78 HV

Same in both: Elastic (Young's) Modulus 45 GPa6.5 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
1.83 g/cm³0.07 lb/in³

Melting Point (Solidus)

510°C950 °F
520°C968 °F

Liquidus Temperature

620°C1,148 °F
635°C1,175 °F

Thermal

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

Thermal Conductivity

80 W/m·K46.2 BTU/hr·ft·°F
121 W/m·K69.9 BTU/hr·ft·°F

Latent Heat of Fusion

370 J/g159 BTU/lb
350 J/g150 BTU/lb

Max Service Temperature (continuous)

120°C248 °F
150°C302 °F

Min Service Temperature

-100°C-148 °F
-80°C-112 °F

Same in both: Specific Heat Capacity 1,000 J/kg·K0.24 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 26 µm/m·K14.4 µin/in·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

13.8 % IACS
28 % IACS

Electrical Resistivity

1.25×10⁻⁷ Ω·m4.92 µΩ·in
6.1×10⁻⁸ Ω·m2.4 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

22 / 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.

Weldability

70 / 100
25 / 100

Formability (cold)

25 / 100
30 / 100

Castability

50 / 100
40 / 100

Polishability

55 / 100
60 / 100

Same in both: Machinability 95 / 100 · Machinability Rating (AISI 1212 = 100 %) 400% · Brazeability / Solderability 20 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

350 MJ/kg150,473 BTU/lb
300 MJ/kg128,977 BTU/lb

Typical Recycled Content

25%
20%

Same in both: Embodied Carbon (primary production) 30 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

172 kN·m/kg
186 kN·m/kg

Specific Stiffness (E / density)

25 MN·m/kg
24.6 MN·m/kg

Modulus of Resilience

588 kJ/m³
751 kJ/m³

Thermal Diffusivity

44.4 mm²/s
66.1 mm²/s

Thermal Shock Resistance Index

21
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.

701001502001.41.51.61.71.8Density (g/cm³)Yield strength (MPa) — log scaleZK60AAZ61B

Manufacturing and finishing

CapabilityAZ61BZK60A
Default condition—F
Relative cost$$ Standard$$ Standard
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 0.8 µmRa 0.8 µm

Both are offered for CNC machining and Sheet metal. Both take the same 7 finishes: Anodizing Type II, Chem Film (Alodine), E-Coating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Painting, Powder Coating.

AZ61B vs ZK60A — frequently asked

Is ZK60A stronger than AZ61B?

Yes. ZK60A has a typical yield strength of 260 MPa (37.7 ksi) against 230 MPa (33.4 ksi) for AZ61B — about 13% more. Tensile strength is 340 MPa (49.3 ksi) vs 310 MPa (45 ksi).

Which is cheaper, AZ61B or ZK60A?

Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which welds better, AZ61B or ZK60A?

AZ61B. Its weldability rates very good (70/100) against poor (25/100) for ZK60A.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AZ61B and ZK60A 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.