Everyone has been there. You pass a construction site, look at the metal structures, and ask yourself how it’s all held together. There are many ways that metals can be held together. Some structures use attachments like rivets to hold the metal pieces together while others use methods that involve melting a part of the metal, such as brazing and welding.
What’s the difference between dip brazing and welding? Keep reading to find out the difference and some of the pros and cons of each.
Difference Between Brazing And Welding
Dip brazing and welding are similar processes in that they both join pieces of metal together, but they work in different ways and have different applications. Here we will compare dip brazing, soldering, and welding to see the difference.
Welding
In welding, two pieces of metal melt at their ends and physically fuse together. This means the metals must have similar melting points in order to join together. They must stay at these high temperatures at the joint during the welding process. A filler is sometimes used in welding to join the pieces of metal together. However, the filler must also have a similar melting point which limits the type of metal that the filler can be.
Usually, the two pieces of metal to be joined are held close together while a targeted welding torch applies heat at a small part of the joint. The torch melts the filler or the metal itself so that the two pieces fuse together. Sometimes pools of melted material can form at the bottom
Brazing
In brazing, a filler metal joins the ends of two pieces of metal. The two pieces come close together so that the filler can come between them. Then, capillary action causes the filler to flow into the gap between the two pieces of metal. Typically, a relatively low melting-point filler is used because only the filler needs to melt. This means the pieces of metal being joined remain intact throughout the brazing process.
The filler metal is usually an alloy of metals that bonds to both of the metals being joined. A chemical called flux helps the filler metal flow through the gap between the two pieces of metal. The flux also keeps the metals clean and removes things like oxides so that a good seal forms between the metals. The method of brazing we are concerned with, called dip brazing, completely submerges the metals being joined into a bath of filler.
Soldering
Soldering contains some aspects of both welding and brazing, but it also has some differences. Like in welding, soldering uses a soldering iron to apply heat at a targeted location. Similar to brazing, however, soldering operates at low temperatures. The American Welding Society has a strict definition when it comes to metals that can be solders.
Any solder must have a melting point below about 840 degrees Fahrenheit or about 450 degrees Celsius. Many metals can be solders, including things like gold, silver, copper, or brass. These solders act as the filler, joining the two pieces of metal together. In addition to joining metals together, soldering can also connect elements of electrical circuits. This makes the technique especially important in electronics and computers.
Advantages And Disadvantages
There are many types of steel fabrication services from laser cutting to chemical film coating, but they all have advantages and disadvantages. Depending on your particular application, dip brazing, welding, or soldering might be the best choice.
Welding
Welding has many advantages over dip brazing and soldering, but it also has some disadvantages. Welding produces the strongest joints since the metals are physically fused together.
Welded joints are better at dealing with high-temperature settings since all of the components have a relatively high melting point. Some welding processes are good at joining together pieces of metal with different widths. Welding also has some disadvantages. Since the joined metals melt, they lose some of their structural integrity. The heat from melting can sometimes cause distortion or stress in the metals. Since the metals are melted together, they have to be similar pieces of metal in order to fuse together properly.
Dip Brazing
Dip brazing has many advantages over welding and soldering depending on your application. Since dip brazing doesn’t join the two pieces of metal themselves, it is great for joining different metals together, especially ones with different melting points. Since the filler metal usually has a lower melting point than either of the other metals, it uses less energy compared to welding because the metals are at a lower temperature.
Since dip brazing doesn’t melt the metals being joined, they keep their physical properties and strength. Joints made by dip brazing can be as strong as those made by welding, and they are almost always stronger than those made by soldering. Dip brazing also leaves a cleaner and smoother looking joint compared to welding.
Some disadvantages to brazing are that these joints don’t do well in high-temperature settings since the filler has a lower melting point. In addition, the flux material may contain toxic elements.
Soldering
Since soldering occurs at such a low temperature, the amount of energy required for this procedure is much less than that of brazing or welding. Soldering shares the advantage of joining together different types of materials with brazing. Because soldering is such a delicate and targeted process, it can join together very thin pieces of metal that would not be possible to join with brazing or welding.
However, this does give soldering the disadvantage of having lower strength between joints. Soldered joints should not be in a setting where they have to bear a load. This also means they cannot work on large pieces of material. Soldering shares the disadvantage of not doing well in high-temperature settings with brazing because the melting points of the metals are so low.
Next Steps
Now that you know the difference between dip brazing and welding and some of their advantages and disadvantages, feel free to contact us for more information about how we can help with your next project.
If you enjoyed this article, please check out some of our other great articles from fabrication to machining services.
