Welding aluminum to steel is a challenging task that requires skill and precision. It is possible to weld aluminum to steel, but it needs to be done with care. The process can be complicated and time-consuming, but it can be done successfully if the right techniques are used. In this article, we will discuss the best methods for welding aluminum to steel and how you can make sure that your welds are strong and reliable.
So Can You Weld Aluminum To Steel ?
The answer is aluminum and steel can be welded.
Aluminum alloy has excellent characteristics such as low density, good corrosion resistance, high electrical conductivity and thermal conductivity, and the use of aluminum alloy instead of steel can greatly reduce the quality of welded structures. Steel has good weldability and mechanical properties, and aluminum-steel welded structures have been widely used in automobiles, shipbuilding and other industries.
The melting point of aluminum is 660°C, which is 700-900°C lower than that of steel. During welding, aluminum with a lower melting point melts first. On steel, cooling can cause inhomogeneity in the composition of the weld. The large difference in linear expansion coefficient between aluminum and steel will lead to large residual stress in the welded joint, which will lead to weld cracks.
In order to realize the reliable connection of aluminum and steel, it is necessary to overcome the hindering effect of the oxide film on the surface of aluminum and aluminum alloy to the connection, and to prevent or reduce brittle intermetallic compounds on the interface between aluminum alloy and steel.

How to weld aluminum to steel?
If the steel frame and aluminum alloy are welded by fusion welding, they cannot be welded because the difference in their melting points is too great. At present, the ideal ones are as follows. 1: Friction welding, mainly suitable for shaft-shaped products. 2: Explosive welding, mainly suitable for welding aluminum plate and steel plate. 3: Brazing, mainly using gas welding flame as heat source, melting lead solder for welding. In addition, aluminum electrodes can be used for welds with low requirements for welds. We have used MG400 electrodes to weld aluminum and steel with low requirements, and the effect is not bad. Using this method, the price is low, the speed is fast, and it is very convenient to use, but the impact resistance of the weld is not ideal, and it needs to be preheated before welding for relatively large aluminum parts. If the welding method of low temperature brazing is used, it can be welded well, but the steel frame and aluminum alloy need to be welded at the angle of fillet joint or socket joint, and the welding material is Q303B welding.