Research advances on weldability of Mg alloy and other metals worldwide in recent 20 years

With the strict regulation of automobile emissions by the state, many automobile manufacturers begin to work hard on automobile quality. Magnesium (Mg) alloy is one of the commonly used materials in automobile lightweight design, In the use of Mg alloys, welding appears to be a priority. Mg alloys have poor weldability with other metals due to their physical and chemical properties, and are prone to welding defects such as cracks and depressions during the welding process. This paper mainly introduces the properties, applications, and several main welding methods of Mg alloys (Fusion welding, friction welding, diffusion welding, explosive welding, etc.). And analyzed and discussed the advantages and disadvantages of various welding methods and precautions, and put forward some methods to reduce the difficulty of welding and improve the quality of joints.