Zinc Alloy Zamak 3 vs Zamak 7
Zinc Alloy · grade comparison
Zinc Alloy Zamak 3 and Zamak 7 are both zinc alloy grades. Both yield at about 221 MPa — strength does not separate them. Zamak 7 is the more ductile: elongation 13% versus 10% for Zamak 3. On the shop floor, Zamak 3 machines more easily (excellent vs very good) and Zamak 3 sits in a lower cost tier (budget, $) than Zamak 7 (standard, $$).
Zamak 3Choose it when the part is machined in volume, or when cost is the deciding factor.
Zamak 7Choose it when the part is bent, formed or impact-loaded.
Zamak 3 vs Zamak 7: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all zinc 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 zinc 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.
Shear Modulus
Bulk Modulus
Yield Strength (0.2% offset)
Elongation at Break
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 96 GPa13.9 Msi · Poisson's Ratio 0.27 · Tensile Strength (Ultimate) 283 MPa41 ksi · Compressive Strength 414 MPa60 ksi · Shear Strength 214 MPa31 ksi · Charpy V-Notch Impact (RT) 58 J42.8 ft·lbf
Physical
Density and transition temperatures.
Same in both: Density 6.6 g/cm³0.24 lb/in³ · Melting Point (Solidus) 381°C718 °F · Liquidus Temperature 387°C729 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 113 W/m·K65.3 BTU/hr·ft·°F · Specific Heat Capacity 419 J/kg·K0.1 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 27.4 µm/m·K15.2 µin/in·°F · Latent Heat of Fusion 110 J/g47.3 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 27 % IACS · Electrical Resistivity 6.4×10⁻⁸ Ω·m2.52 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Brazeability / Solderability
Same in both: Castability 97 / 100 · Polishability 85 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Embodied Water
Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Typical Recycled Content 25%
Common Calculations
Ratios derived from the values above.
Modulus of Resilience
Same in both: Specific Strength (UTS / density) 43 kN·m/kg · Specific Stiffness (E / density) 14.5 MN·m/kg · Thermal Diffusivity 40.9 mm²/s · Thermal Shock Resistance Index 12
Strength versus weight
Yield strength against density for every zinc alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | Zamak 3 | Zamak 7 |
|---|---|---|
| Casting & forging | Yes | — |
| Default condition | As Cast | As Cast |
| Relative cost | $ Budget | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both are offered for CNC machining. Both take the same 6 finishes: Chrome Plating, Copper Plating, E-Coating, Nickel Plating, Painting, Powder Coating.
Zamak 3 vs Zamak 7 — frequently asked
What is the difference between Zamak 3 and Zamak 7?
Zinc Alloy Zamak 3 and Zamak 7 are both zinc alloy grades. Both yield at about 221 MPa — strength does not separate them. Zamak 7 is the more ductile: elongation 13% versus 10% for Zamak 3.
Which is cheaper, Zamak 3 or Zamak 7?
Zamak 3 is the lower-cost material: it sits in the budget tier ($) while Zamak 7 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, Zamak 3 or Zamak 7?
Zamak 3. Its machinability rates excellent (90/100) against very good (80/100) for Zamak 7; for welding the order is Zamak 3 first (poor, 20/100) then Zamak 7 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Zamak 3 and Zamak 7 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.