Let’s look at some of the fundamental aspects you need to know about Zamak 7 alloy.
- What Is The Composition Of Zamak 7?
- What Are The Properties For Zamak 7?
- Where Is Zamak 7 Material Applied?
- How Does Zamak 7 Compare To Zamak 3?
- What Are The Benefits Of The Zamak 7?
- How Can You Check Quality Of Zamak 7?
- Is Zamak 7 Suitable For Die Casting?
- What Are Limitations Of Zamak 7?
- How Strong Is Zamak 7?
- How Does Zamak 7 Compare To Aluminum Alloys?
What Is The Composition Of Zamak 7?
Zamak 7 also known as Zinc alloy 7 is a combination of aluminum, magnesium and copper with zinc acting as base material.
It derives its name from its material’s set composition range; Zinc (Z), Aluminum (A), Magnesium (MA), Kupfer (Copper).
Zamak 7 alloy contains less quantities of magnesium with better ductility than Zamak 3 thus is considered a high-purity alloy. The added alloys impurities are controlled by adding small quantities of nickel which also reduces inter-granular corrosion.
The elements which make up Zamak 7 material include the following and in a given quantity as follows:
|Element||Quantity in percentage (%)||Element Properties|
|Iron (Fe)||0.075 max|
|Nickel (Ni)||0.005-0.02||Controls impurities|
|Magnesium (Mg)||0.005-0.02||Low Mg Increases fluidity|
|Lead (Pb)||0.003 max|
|Tin (Sn)||0.002 max|
What Are The Properties For Zamak 7?
Zamak 7 possesses physical, chemical and mechanical properties due to its element composition.
Physical properties of Zamak 7 are as follows measured in metric and imperial values;
|Physical property||Metric value||Imperial value|
|Melting range||381—387 °C||718—729 °F|
|Coefficient of thermal expansion||27.4 μm/m-°C||15.2 μin/in-°F|
|Thermal conductivity||113 W/m-K||784 BTU-in/hr-ft2-°F|
|Electrical resistivity||6.4 μΩ-cm||2.5 μΩ-in|
|Specific heat capacity||419 J/kg-°C||0.100 BTU/lb-°F|
|Casting temperature||395—425 °C||743—797 °F|
The chemical properties of Zamak 7 include the individual elements which make up zinc alloy 7 unique. Each element possesses a unique property that affects the final property of Zamak 7.
Mechanical properties of Zamak 7 contribute to its application in different areas such as in manufacturing of appliances, die cast toys, etc.
Some of those properties include:
|Mechanical property||Metric value||Imperial value|
|Shear strength||214MPa||31,000 psi|
|Elongation at fracture||13-14%|
|Comprehensive yield strength||221MPa||32Psi|
|Impact strength||58.0 J||42.8ft-lbf|
|Fatigue strength (reverse bending 5×108 cycles) 47.0 MPa||6,820psi|
|Yield strength||285 MPa||41,300 psi|
|Ultimate Tensile strength||285MPa||41,300 psi|
Where Is Zamak 7 Material Applied?
Zamak 7 is highly ductile, fluid and with improved surface finish as a result of the strictly controlled alloy impurities.
It is therefore applied in different areas such as:
- Die casting for making thin walled components necessary for good surface finish.
- Manufacture of some firearms
- Used for damping and vibration attenuation
- Making of appliances such as door locks, handle, key chains, etc.
How Does Zamak 7 Compare To Zamak 3?
Zamak 7 and Zamak 3 are both zinc alloys composed of different alloy components with zinc as the base metal.
Zamak 7 however has low content of magnesium (0.02) element thus making it more fluid compared to Zamak 3 (0.05).
Both Zamak 7 and Zamak 3 have aluminum content of 4% with the other elements contents varying.
Zamak 3 is the standard zinc alloy due to its balanced element composition, physical and mechanical properties. As a result, Zamak 3 is widely used in die casting due to stability and longevity compared to Zamak 7.
What Are The Benefits Of The Zamak 7?
Zamak 7 boost of several advantages due to its mechanical and physical properties such as rigidity, strength and toughness. All this combined property contributes to better performance and economical castability.
- Strength and ductility
Zamak 7 is highly strong and with superior elongation properties thus making it formidable for use in designs and bending operations.
Zinc alloys are rigid and equally elastic in characteristic just like other materials. However, their level of rigidity is far superior than other die cast.
Zamak 7 is highly resistance to impact and strong compared to other materials like plastics, aluminum alloys and grey cast iron.
Zinc alloy is non-sparking making Zamak 7 ideal for use in hazardous areas such as coal miners, refineries, etc.
- Easy finishing
Zamak 7 casting material can be easily polished, chromate or anodized or plate painted for decorative purposes.
- Long shelf-life
Zamak 7 has low casting temperature making it experience less thermal shock when working with it. This extends the casting life of zinc alloys compared to aluminum alloy.
- Thin wall castability
Thin wall castings can be made on zinc due to high-casting fluidity of Zamak 7.
Due to trouble free mechanization of zinc material without wear and tear during use, makes it a great tool.
Zinc alloy are known to have clean melting points which is toxic free making it a recyclable and reusable material.
How Can You Check Quality Of Zamak 7?
One of the ways to confirm the quality of Zamak 7 is by checking its elements quantities.
Excessive presence of impurities will interfere with the corrosive property hence making it loose this characteristic.
Is Zamak 7 Suitable For Die Casting?
Yes, it is.
This is because Zamak 7 is has high fluidity thus allowing thin wall casting regardless of the process.
What Are Limitations Of Zamak 7?
- Zamak 7 is heavy in weight hence it is not applicable in lightweight operations.
- Very high temperature can easily damage zinc casting tensile strength making it fragile.
- The impact strength of Zamak 7 decreases significantly with a drop in temperature.
- Other elements in excess quantities such as lead and tin decreases its corrosive property.
How Strong Is Zamak 7?
Zamak 7 has an ultimate tensile strength of 41,300 psi which makes using it during bending, elongation operations possible.
Besides, they have an impact resistance of 58.0 J making them tougher than other alloys such as aluminum alloys.
How Does Zamak 7 Compare To Aluminum Alloys?
- Zamak 7 is made from zinc alloys classification and other elements in different quantities with zinc as base material. Aluminum alloys is derived from aluminum alloy classifications and other elements.
- Zamak 7 die casting is easier to achieve without additional machining compared to aluminum alloy casting.
- Zamak 7 has excellent corrosion resistance compared to aluminum alloy.
- Zamak 7 has better mechanical properties than aluminum alloy.
- Zamak 7 has better fluidity than aluminum alloy thus can be used to make thinner parts of die casting.
- Zamak 7 is a heavy weight material and durable whereas aluminum alloy is light weighted structural material.