Over the years, the application of magnesium alloys has been affected by three kinds of doubts: one is high cost (expensive raw materials and recycling), the other is corrosion-prone, and the third is high flammability and explosiveness.

In fact, although the energy consumption of molten magnesium is greater than that of molten zinc, it is smaller than that of molten aluminium. Today's technology of flux-free magnesium melting and adding sulfur fluoride (SF6) have been able to control the loss of magnesium melting to a minimum. At the same time, the good cutting performance of magnesium alloys, the controllable minimal die casting error and the high die casting productivity make the application cost of magnesium greatly reduced.

The corrosion problem of magnesium alloy parts has been solved by simple technology such as adding gaskets and new surface treatment technology. The flammability of magnesium has also been solved by various measures. In fact, magnesium castings are not as flammable as magnesium powder, and corresponding measures have been taken for melting magnesium alloys or high flammability in high speed cutting.

Therefore, the above doubts need not be worried in today's technological conditions, and the following unique advantages of magnesium alloys make this new star in the field of materials more brilliant.

Advantages of Magnesium Alloy over Other Alloys

Aluminum alloy is the most commonly used bicycle material.

The reality is that China's total reserves of aluminium resources and ores account for only 2.96% of the world's total reserves, ranking ninth in the world, and need a large number of imports every year.

It is estimated that, according to the current development rate, the domestic aluminium ore resources will be exhausted in about ten years. In the case of exhaustion of aluminium resources, which material should we find to replace? Magnesium is one of the most abundant light metal elements on the earth, and China is one of the countries with the richest magnesium resources in the world. The total reserves of magnesium resources and ores account for 21.7% of the world's total reserves, ranking first in the world, and also the largest exporter of magnesium resources.

The density of magnesium is only 1.74g/cm3, about 2/3 of aluminium, 2/5 of titanium and 1/4 of iron. Magnesium alloys are magnesium based alloys with other elements added. Magnesium alloys are 36% lighter than aluminium alloys, 73% lighter than zinc alloys and 77% lighter than steel. The elongation and impact resistance of magnesium alloy are better than that of die-casting aluminum alloy.

In particular, the modulus of elasticity, which is a measure of the resilience of an object to elastic deformation, is explained here. Under a certain load, the lower the elastic modulus is, the larger the elastic modulus deformation is, the smaller the stiffness is, the better the flexibility of the material is easy to deform; the higher the elastic modulus is, the smaller the elastic modulus deformation is, the greater the stiffness is, the material is not easy to deform, and the stronger the brittleness is.

Magnesium alloys have very high die casting productivity.

It can be concluded that die-cast magnesium alloys have good fluidity as die-cast aluminum alloys and die-cast zinc alloys, and their crystallization latent heat and thermal conductivity are lower than A380, and their solidification range is larger than A380. Therefore, the die-casting magnesium alloy has good filling ability, the solidification speed is faster after filling, and the thermal shock to the die-casting mold is smaller. It can be used for thin-walled die-casting without hot cracking and undercasting defects, and can reduce the thermal fatigue phenomenon of the die-casting mold, prolong the service life of the die-casting mold, shorten the retention time of the die-casting castings, and die-casting production. The production rate is about 75% faster than that of aluminium alloy.

In addition to the above characteristics, the advantages of magnesium alloys are also reflected in good heat dissipation and corrosion resistance to organic matter and alkali, which are completely different from the flammability, self-explosion, instability and strong activity of pure magnesium.

Advantages of Magnesium Alloy over Carbon Fiber Materials

Now in the field of bicycle materials, apart from discussing alloys and carbon fibers, we all know that the strength of carbon fibers under the same weight is much higher than that of ordinary metals, but the relatively high price creates a certain threshold for it.

According to people in bicycle manufacturing industry, carbon fibers, after all, are not as suitable for mass production as magnesium alloys because of their many manual ingredients. Therefore, it costs a lot of money, takes a long time and requires a high level of technology. These factors directly affect the price of finished products, which makes end-users spend more money.

On the other hand, environmental protection is an important topic in all walks of life, and the damage of carbon fibers to the environment is considerable. A study released by Toyota Motor in 2010 showed that carbon fibers produced a large amount of waste gas and sewage in the raw material treatment stage, while the processing process emitted more carbon dioxide, and its production process could lead to various respiratory diseases and skin diseases of workers. After carbon fiber products are discarded, they will exist in soil and water for a very long time, and it is very difficult to degrade, which further pollutes the earth. Therefore, whether carbon fibers are suitable green materials is still unknown.

Magnesium alloys are emerging environmental protection materials in the 21st century. Magnesium alloys are also classified as environmental protection industry abroad. Its performance of non-polluting, recyclable and reusable environment is quite satisfactory.

Policy Advantages of State Support

In the current 13th Five-Year Plan, the state has listed magnesium alloys as very important materials, so the guidance and support in this regard is very strong. For example, in Henan and Shanxi, where there are large reserves of magnesium resources, the state's subsidies are very generous. In fact, in addition to the exploitation of raw materials, there are also in the processing, as long as it is related to magnesium alloys, the country will give a great degree of help, with millions of money.

"Developing High-performance Magnesium Alloys with light weight, high strength, large specifications, high temperature resistance, corrosion resistance and fatigue resistance as the development direction, focusing on meeting the needs of large aircraft, high-speed railway and other transportation equipment, accelerating the preparation and deep processing technology development of magnesium alloys, and developing magnesium alloys in automotive parts, rail trains and other fields.