With the continuous development of science and technology, new materials, new processes and new equipment appear constantly.The connection of heterogeneous metals has attracted extensive attention from all walks of life.As one of the main methods of material connection, welding plays an important role in the connection process of heterogeneous metals.Due to the great difference in chemical composition, physical properties, metallurgical structure and mechanical properties of materials, welding of heterogeneous metals is more complicated than welding of the same metal.
The first is the bonding performance. The bonding performance of welded components refers to the difficulty of forming a joint without defects and with good bonding performance in the welding process. Only on the basis of good bonding performance, the welded components can show good use performance.

In order to ensure good bonding performance of smoke joint members in the welding process, appropriate welding methods should be selected, welding parameters should be optimized, filling materials or intermediate layers should be selected, and relevant measures such as preheating before transmission and heat treatment after welding can also be considered according to specific conditions.The second is the performance of the welded joint. The performance of the welded joint refers to whether the welded members can meet the use requirements in the process of using. If the welded members can meet the use requirements, they have better performance; otherwise, the welded joint does not have good performance.

The weldability of heterogeneous metals is also relative. In general, there is no heterogeneous material that cannot be welded at all. The research shows that the weldability of heterogeneous metals can be improved by the following measures.
For example, welding method, welding process, filling material or intermediate layer, preheating before welding and heating after welding, form and size of welding joint will have great influence on the bonding performance and service performance of welding joint of different metals.
In the actual production, according to the characteristics of the jointed materials and welding characteristics, a reasonable welding process should be formulated, appropriate filling materials and welding methods should be selected, and the operation specifications should be paid attention to during the welding process, so as to prepare for the acquisition of welding joints with good binding performance and use performance.