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Why magnesium?
It is the lightest structural material in existence, with a density of 1.8 g/cm3, 75% lighter than steel and 33% lighter than aluminum, offering the best strength-to-weight ratio of all commonly used structural metals.
Magnesium is the seventh-most abundant element in the earth’s crust, constituting about 2% of it, and the third-most abundant element dissolved in seawater.
It is obtained from seawater, brines and magnesium minerals that offer virtually unlimited reserves, providing an abundant source of raw material.
It is a 100% ecological and fully recyclable material. The magnesium recycling process consumes only 5% of the energy required to obtain the same amount of raw magnesium material.
Magnesium is completely harmless to humans and the environment. It is a fundamental element for life and is therefore used in biomedical applications such as prosthetics.
It has excellent dimensional stability, as well as high impact and dent resistance.
It is a material with exceptional damping capacity and low inertia.
High-purity magnesium alloys offer better corrosion resistance than steel and most aluminum alloys.
Its high capacity to manufacture thin parts allows the production of one-piece structures instead of assembling several components. All this simplifies design, reduces assembly costs, minimizes tooling costs and eliminates welding processes.
It offers faster cycle times in the casting process because less energy is required to reach melting temperature. Also, a longer mold life is obtained since a lower working temperature and the low affinity with the steel reduce the effects of thermal fatigue and erosion of the tooling.
Magnesium characteristics
MECHANICAL CHARACTERISTICS
- Hexagonal mesh structure.
- High strength to weight ratio.
- Good impact resistance.
- High resistance to dents.
- High energy-absorption capacity.
- High vibration-damping capacity.
- Low inertia.
PROCESS CHARACTERISTICS
- Excellent dimensional stability.
- Excellent machinability.
- Excellent dimensional accuracy.
- Excellent casting properties:
- Excellent castability.
- Capacity to achieve thin thicknesses.
- Capacity to manufacture complex geometries.
- Longer mold lifetime.
SPECIAL CHARACTERISTICS
- Good thermal conductivity.
- EMI/RFI protection.
- Non-magnetic.
- Non-toxic.
- 100% Ecological.
- 100% Recyclable.
Mechanical properties of magnesium alloys
Comparing magnesium with other metals
MAGNESIUM VS. ALUMINUM
Advantages of magnesium vs. aluminum:
- 33% lighter than aluminum
- Superior mechanical properties
- Longer life of molds and dies
- Lower energy consumption during production
- Faster machining
- Increased corrosion resistance
- Possibility of manufacturing very thin-walled parts
- Aluminum has been shown to cause similar health problems to heavy metals
MAGNESIUM VS. STEEL
Advantages of magnesium vs. steel:
- 75% lighter than steel
- Integration of components (lower assembly cost)
- Significantly lower tooling costs
- High thermal conductivity
- Superior dimensional stability and repeatability
- Possibility of manufacturing very thin-walled parts
MAGNESIUM VS. PLASTIC
Advantages of magnesium vs. plastic:
- Stronger and more wear-resistant material
- Far superior rigidity
- Increased energy absorption capacity and impact resistance
- Application on parts requiring higher temperatures
- High thermal conductivity
- Possibility of manufacturing very thin-walled parts
- 8 million tons of plastics are dumped in the oceans every year
Magnesium alloys
AZ91D ALLOY
- The most-widely used general-purpose magnesium alloy.
- Main alloying elements: Al and Zn.
- The inclusion of aluminum improves its:
- Mechanical strength.
- Corrosion resistance.
- Castability.
- Typical application in mechanical components where hardness is more important than deformation capacity.
AM SERIES ALLOYS (AM60B AND AM50A)
- Series of alloys with reduced Al content.
- This alloy offers:
- High energy absorption.
- Excellent ductility and consideration to fracture.
- Manganese is included to control the iron content of the alloy.
- Mainly used in components related to safety parts in the automotive and railway field.
AS AE SERIES ALLOYS
- Special alloys for use in higher-temperature service conditions (above 120ºC).
- The AS series is based on the addition of silicon.
- The AE series adds some of the chemical elements called rare earths.
Composition of magnesium alloys
% Al | % Mn | % Zn | % Si (max) | % Cu (max) | % Ni (max) | % Fe (max) | Otros max (%) | |
AZ91D | 8.5 – 9.5 | 0.17 – 0.40 | 0.45 – 0.9 | 0.05 | 0.025 | 0.001 | 0.004 | 0.01 |
AM60B | 5.6 – 6.4 | 0.26 – 0.5 | Max 0.20 | 0.05 | 0.008 | 0.001 | 0.004 | 0.01 |
AM50A | 4.5 – 5.3 | 0.28 – 0.5 | Max 0.20 | 0.005 | 0.008 | 0.001 | 0.004 | 0.01 |
AS41B | 3.7 – 4.8 | 0.35 – 0.6 | Max 0.10 | 0.6-1.4 | 0.015 | 0.001 | 0.0035 | 0.01 |