NEWS

Casting magnesium alloys can be roughly divided into three stages:

(1) The first stage is a basic stage, mainly adding aluminum and zinc, namely Mg-A1-Zn alloy, to magnesium. This type of alloy can achieve tensile strength similar to that of cast aluminum alloy. ZM5 in China, L121 in the UK, and AM80A in the US all belong to this type of alloy, with aluminum as the main added element, while the zinc content is relatively low, mainly because micro porosity is prone to occur when the zinc content increases.

 (2) The second stage is an improvement stage where zirconium is added to magnesium. Common zirconium containing alloy systems include Mg Zn Zr, Mg RE Zr, etc. The main function of zirconium in magnesium alloys is to refine the grain size of magnesium alloys, thereby improving their yield strength and giving them good fatigue resistance and low notch sensitivity. The disadvantage is still due to the wide crystal spacing, which makes it prone to micro porosity and hot cracking. So the most commonly used is Mg Al, a zirconium free die cast magnesium alloy. In addition, in order to improve the high-temperature creep resistance of magnesium alloys, magnesium alloys with rare earth elements as the main component have been developed.

(3) The third stage is the improvement stage. Adding silver to magnesium alloy can enhance the aging strengthening effect after silver alloying, greatly improving the high-temperature strength and creep resistance of magnesium alloy, but it will reduce the corrosion resistance of the alloy.