What’s the difference between soldering, brazing and welding?
All three processes involve the use of heat to join pieces of metal, but there are many differences between the techniques.
Welding is a relatively difficult process which involves heating the metal until it melts – in doing this the two pieces can be joined together to create a strong joint. Often a filler metal is used to create a weld pool, which helps to make the joint even stronger and more durable.
There is a variety of welding techniques and processes, including TIG, MIG and stick welding, which all require slightly different tools and equipment. It takes a great deal of time, training and practice to master the art of welding (especially all the different types), so for welders, it often becomes more than just a hobby.
Brazing differs from welding in that the two pieces of metal which are being joined never actually melt. Brazing does use a filler metal (in a similar way to some welding techniques), which is melted at the join. When this pool of molten metal cools, it hardens into a strong, resilient joint.
As with welding, there are many different brazing techniques, including torch brazing and furnace brazing.
Soldering is very similar to brazing due to the fact that it is only the filler metal which melts, not the pieces of metal which are being joined. However, the most notable difference is that soldering takes place at much lower temperatures than brazing.
Originally, it was common to use lead as the filler metal when soldering, but safer alternatives are used nowadays due to the health risks associated with lead.
The lower temperatures mean that soldering is typically thought of as the safest and easiest technique to master (when compared to welding and brazing), especially because it requires much less specialized safety equipment. In addition, it’s suitable for a range of applications including very fine, detailed work, which is why it’s a popular choice for joining metals in small, delicate, household jobs such as jewelry making and electronics.