Welding, soldering, and brazing are all techniques used for joining pieces of metal together, and each one has its own varied processes and aspects. All of these techniques can also be used to fill gaps in metal parts, in addition to their main function of joining pieces together to create a joint. Soldering, brazing, and welding are al used to create valuable parts and pieces for machinery in a variety of industries. Here’s a closer look at some of the similarities and differences when it comes to each of these three techniques:
Soldering
Soldering is the lowest-temperature option of the three, using fillers like iron, brass, and silver to bond with and join metal parts. Fillers use for soldering melt at a relatively low temperature—450 degrees Celsius—and the bond created from soldering is not as strong as those created by welding or brazing. Typically, soldered joints are not meant to bear loads. However, one of the benefits of soldering is that the low temperatures don’t result in any changes to the mechanical properties of the metals used, which is crucial for a properly functioning joint.
Brazing
Brazing involves heating and melting a braze material, or filler, which joins two pieces of metal. Unlike welding, brazing can be used to join two different metals, but since higher temperatures are involved, the filler material needs to have a lower melting temperature than the metals being joined. Properly brazed joints can be incredibly strong; stronger, in fact, than the metals they join, and it’s rare that the mechanical properties of the brazed joint are affected.
Welding
Welded joints tend to be the strongest, but can result in undesired changes in the properties of base metals used. This is due in part to the extremely high temperatures used in welding—around 3800 degrees Celsius. The changes in the metals due to the extreme heat and cooling processes may wind up weakening the welded joint if the welding is not done correctly or with proper care. Additionally, the two parts being welded together must be the same type of metal, unlike the advantage offered by brazing.
The best technique for the job will depend upon on the type of job itself, in addition to the required durability and function of the joint that is created. While all three of these techniques are highly effective, their different results and processes make them suited for different types of jobs.
