FabDigitFabDigit

Magnesium Alloy AM60B vs ZK40A

Magnesium Alloy · grade comparison

Magnesium Alloy AM60B and ZK40A are both magnesium alloy grades. ZK40A is the stronger of the two: yield strength 145 MPa (21 ksi) against 130 MPa (18.9 ksi) for AM60B, about 12% more; tensile strength follows at 250 MPa (36.3 ksi) vs 225 MPa (32.6 ksi). In exchange, AM60B is the more ductile: elongation 8% versus 5% for ZK40A. ZK40A conducts heat better (117 W/m·K vs 61 W/m·K). On the shop floor, AM60B welds better (fair vs poor) and AM60B sits in a lower cost tier (standard, $$) than ZK40A (premium, $$$).

AM60BChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

ZK40AChoose it when strength drives the design.

AM60B vs ZK40A: properties

AM60BZK40A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

17 GPa2.5 Msi
16.5 GPa2.4 Msi

Tensile Strength (Ultimate)

225 MPa32.6 ksi
250 MPa36.3 ksi

Yield Strength (0.2% offset)

130 MPa18.9 ksi
145 MPa21 ksi

Elongation at Break

8%
5%

Compressive Strength

130 MPa18.9 ksi
300 MPa43.5 ksi

Shear Strength

140 MPa20.3 ksi
145 MPa21 ksi

Fatigue Strength (Endurance Limit)

70 MPa10.2 ksi
85 MPa12.3 ksi

Fracture Toughness (K_IC)

16 MPa·√m14.6 ksi·√in
14 MPa·√m12.7 ksi·√in

Charpy V-Notch Impact (RT)

6 J4.4 ft·lbf
4 J3 ft·lbf

Hardness, Brinell

62 HB
65 HB

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)

540°C1,004 °F
550°C1,022 °F

Liquidus Temperature

615°C1,139 °F
635°C1,175 °F

Thermal

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

Thermal Conductivity

61 W/m·K35.2 BTU/hr·ft·°F
117 W/m·K67.6 BTU/hr·ft·°F

Specific Heat Capacity

1,020 J/kg·K0.24 BTU/lb·°F
1,000 J/kg·K0.24 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

25.6 µm/m·K14.2 µin/in·°F
27 µm/m·K15 µin/in·°F

Latent Heat of Fusion

373 J/g160 BTU/lb
370 J/g159 BTU/lb

Same in both: Max Service Temperature (continuous) 120°C248 °F · Min Service Temperature -100°C-148 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

13.5 % IACS
29 % IACS

Electrical Resistivity

1.25×10⁻⁷ Ω·m4.92 µΩ·in
6×10⁻⁸ Ω·m2.36 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-1.6 V
-1.55 V

Corrosion Resistance

30 / 100
20 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

500%
400%

Weldability

40 / 100
30 / 100

Castability

92 / 100
55 / 100

Brazeability / Solderability

20 / 100
15 / 100

Polishability

55 / 100
45 / 100

Same in both: Machinability 95 / 100 · Formability (cold) 20 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

330 MJ/kg141,875 BTU/lb
290 MJ/kg124,678 BTU/lb

Embodied Carbon (primary production)

26 kg CO₂/kg
28 kg CO₂/kg

Typical Recycled Content

30%
15%

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

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

125 kN·m/kg
137 kN·m/kg

Specific Stiffness (E / density)

25 MN·m/kg
24.6 MN·m/kg

Modulus of Resilience

188 kJ/m³
234 kJ/m³

Thermal Diffusivity

33.2 mm²/s
63.9 mm²/s

Thermal Shock Resistance Index

12
24

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 scaleAM60BZK40A

Manufacturing and finishing

CapabilityAM60BZK40A
CNC machiningYes—
Default conditionAs Cast—
Relative cost$$ Standard$$$ Premium
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—

AM60B vs ZK40A — frequently asked

Is ZK40A stronger than AM60B?

Yes. ZK40A has a typical yield strength of 145 MPa (21 ksi) against 130 MPa (18.9 ksi) for AM60B — about 12% more. Tensile strength is 250 MPa (36.3 ksi) vs 225 MPa (32.6 ksi).

Which is cheaper, AM60B or ZK40A?

AM60B is the lower-cost material: it sits in the standard tier ($$) while ZK40A is premium ($$$). 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, AM60B or ZK40A?

AM60B. Its weldability rates fair (40/100) against poor (30/100) for ZK40A.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AM60B and ZK40A 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.