Magnesium alloy and aluminum alloy are widely used in CNC machining, but many people don’t know the difference between magnesium alloy and aluminum alloy. Although they know that they are different, they don’t know where the specific difference is. This article The article will take you to a preliminary understanding of the difference between these two alloy materials!
Magnesium alloy
The density of magnesium is only 1.8g/cm3, which is the lightest of the three metals, which also makes magnesium alloys 30% lighter than aluminum alloys and 80% lighter than steel. At the same time, it has an excellent strength/weight ratio, with a yield strength of 160 MPa and a tensile strength of 240 MPa, making it widely used in electronic products, aerospace and other fields that are sensitive to quality and strength. .
Under the premise of maintaining a good structure, the magnesium alloy allows the wall thickness of the casting to be as low as 0.6 mm, which cannot be achieved by plastics and aluminum alloys, and the magnesium alloy is easy to die-cast and has better machinability, so it is more Suitable for mass production. Magnesium metal itself has excellent shock absorption performance and can absorb a large amount of vibration and noise, so it is very suitable for manufacturing the backplane of LCD display.
Aluminum alloy
Aluminum alloy is a general term for a series of aluminum-based alloys. The main metal elements are copper, silicon, magnesium, zinc and so on. Aluminum alloy has low density, but its specific strength is close to high-quality steel, second only to alloy. Good plasticity, can be processed into various profiles. Corrosion resistance is very prominent.
Aluminum alloys can be divided into deformed aluminum alloys and cast aluminum alloys according to processing methods. Deformed aluminum alloys can be divided into non-heat treatable aluminum alloys and heat treatable aluminum alloys. Heat treatment can help the alloy to obtain better mechanical properties, physical properties and corrosion resistance. The cast aluminum alloy can be divided into aluminum-silicon alloy, aluminum-copper alloy, aluminum-magnesium alloy and aluminum-zinc alloy according to the metal composition.
There is not much difference between aluminum alloy and magnesium alloy, but the density of aluminum alloy is slightly inferior, and the viscosity is stronger. However, compared with magnesium alloy, aluminum alloy can be heat treated, and its welding performance is better.
The difference between magnesium alloy and aluminum alloy
Different tensile strength
The strength of the frame made of magnesium alloy material of the same volume is not as strong as that of aluminum alloy. To achieve the strength of the frame, the material thickness and pipe diameter must be increased. Therefore, there is no advantage in comparing magnesium alloy with aluminum alloy in terms of weight.
Different fatigue strength
Taking the frame as an example, the durability of the frame made of magnesium alloy material of the same volume is worse than that of the aluminum alloy frame. It is also a fatal shortcoming of magnesium alloys.
As the number of rides increases, the number of stress occurrences will increase, and the strength will decrease significantly, and even the life of the frame will not exceed 2-3 years, so professional riders rarely use magnesium alloy frames. If they are used in competitions, It is also calculated and replaced in the form of discarding the mileage.
Different metal oxidizing properties
The periodic table of elements clearly shows that magnesium alloys are more susceptible to oxidation and corrosion than aluminum alloys.
Different manufacturing costs
Because magnesium alloy is an active metal, there are higher requirements for manufacturing equipment and environment, resulting in high manufacturing costs, and the cost performance of the produced bicycle frames is far lower than that of aluminum alloy frames.
Hope the above content is helpful to you.
