Aluminum alloy advanced welding process
Aluminum alloy is a material of great economic value with excellent formability and weldability. It has been widely used in various fields. In the welding process of aluminum alloy, however, the hardening of the welded joint easily occurs, causing the performance of the welded joint to deteriorate. Therefore, various advanced aluminum alloy welding processes have been developed and adopted.
Arc welding process is a traditional welding process. In order to reduce the hardness of the weld joint, the small current can be used to obtain the soft bead surface, or large current can be used to fill large plastic beads. The small current arc welding method of fine grain aluminum alloy welding can get a better plasticity and less carbon absorption. However, in small current arc welding, the thermal input is small, so the welding time is long.
Moreover, the heat input between the two heat elements is large, there are many spatter at the same time, making the hot crack at the weld interface prone to occur. The solution to this problem is to increase the amount of aluminum alloy filler metal and reduce the amount of heat input during welding. Furthermore, as the filler metal melts, the weld joint should be wiped off using wet cloth, which can prevent the aluminum electrode from burning too much and reduce the spatter.
Gas Metal Arc Welding (GMAW) process is a wire welding process, which is adopted to reduce the hardening of the weld joint. Compared with traditional arc welding, the GMAW process has higher welding speed and welding heat input, so it can avoid the hardening and cracking of the weld joint.
In addition, filler metal can be used in GMAW process, which is beneficial to enhance the anti-corrosion performance of welded joint especially in outdoor environment. Some non-standard GMAW point and short-circuit welding processes are also used in aluminum alloy welding field. Through introducing new technology, the welding standard of semi-automatic and automatic welding of aluminum alloy can be effectively improved.
Laser Welding is another advanced aluminum alloy welding technology. Laser is a method for heat treatment of the material, making it have high depth/width ratio, and low heat input and weld penetration depth. The laser welding machine can adjust laser power, welding current, welding speed and so on. It has the advantages of small deformation, low heat input and small weld width. Because of its advantages, laser welding is widely used in welding thin plate.
In conclusion, using aluminum alloys in construction has many advantages and good performance, but it can be hard to weld. Therefore, it is necessary to use various advanced welding processes to reduce the hardness of the weld joint and improve welding performance. Through the introduction of new welding technologies and materials, the welding standard of aluminum alloy products can be improved, achieving excellent welding quality and ensuring safety of structure.
