Zamak 27 / ZnAl27Cu2 / ZL-27
Zamak 27, or zinc aluminum alloy, contains significantly more aluminum than the Zamak group of alloys. The number 27 represents the approximate percentage of aluminum
It is extremely difficult to handle and has poor die filling characteristics, which can be offset by simplifying the casting design.
Zamak 27 is 40% stronger and harder than typical aluminum die cast alloys and also offers bearing properties not seen in other alloys
Zamak 27 contains 27% aluminum content and is the strongest of the Zamak series
• Zamak 27 has the highest aluminum content, highest strength, highest melting point, and lowest density of the zamak group
• This zinc alloy exhibits excellent bearing properties, which allow bearings to be designed into the casting of some applications
• Its relatively high casting temperature requires the cold-chamber process
Zamak 27 Chemical Analysis
| Analysis ( %) | Zamak 27 / ZnAl27Cu2 |
|---|---|
| Al | 25.5 – 28.0 |
| Cu | 2.0 – 2.5 |
| Mg | 0.012 – 0.020 |
| Pb | ≤0.005 |
| Fe | ≤0.07 |
| Cd | ≤0.005 |
| Sn | ≤0.002 |
| Si | ≤0.04 |
| Ni | ≤0.001 |
Zamak 27 General Mechanical Properties
| Mechanical Properties | Metric Value |
|---|---|
| Ultimate Tensile Strength | 421 MPa |
| Yield Strength | 379 MPa |
| Impact Strength | 5 J |
| Elongation % in 2 | 1 – 3 |
| Shear Strength | 325 MPa |
| Compressive Yield Strength | 385 MPa |
| Fatigue Strength (reverse bending 5×108cycles) | 145 MPa |
| Hardness | 105 – 125 Brinell |
Zamak 27 General Physical Properties
| Physical Properties | Metric Value |
|---|---|
| Solidification Range (melting range) | 376 – 484 C |
| Density | 5.0 kg/dm3 |
| Coefficient of Thermal Expansion | 26.0 μm/m-°C |
| Thermal Conductivity | 125.5 W/mK |
| Specific Heat Capacity | 534 J/kg-°C |
