Welding supplies are used for different purposes than soldering and brazing supplies. Whether you’re soldering your safety gas valve or welding an outdoor fireplace, you should understand the various differences among welding, soldering, and brazing.

The main differences between welding, soldering, and brazing are the temperatures and heat source used when carrying them out. Continue reading to learn more about the differences among welding, soldering and brazing.

What is Welding?

Welding describes the fabrication process that joins two or more parts together using high heat, pressure, or both. Welding melts two pieces of material together and lets them cool, which results in fusion. Welding typically involves metals and thermoplastics, but can be used on wood. Filler materials can also be used to fill any gaps.

The bond created with welding can withstand numerous forms of stress and the two metals must be similar. For example, you can’t weld steel and copper. The temperature must be high to weld the material but it can’t be too high because it will change the characteristics of metal and weaken the weld.

There aren’t two welding projects that are exactly the same and there are different types of welding depending on the materials you use.

There are four types of welding commonly used.

1. Gas metal arc welding

This type of welding is also known as MIG welding and in this type of welding, an electric arc is formed between the metal and the wire electrode. This applies heat to the metal pieces. When this happens, the parts fuse and melt together, which forms a permanent bond.

2. Shielded metal arc welding

Shielded metal arc welding is also known as flux shielded arc welding or stick welding and it forms the weld with a flux-coated electrode, which is a rod or metal stick held in an electrode holder that’s connected to a power source. Electricity passes through the electrode and touches the base metal, forming a gas between the metal being welded and the electrode.

3. Flux-cored arc welding

Electric arcs unite a continuous filler metal electrode with the base material. When the welding process occurs, the shield gas provided by the flux projects the weld pool from oxidation and other elements in the atmosphere.

4. Gas tungsten arc welding

Gas tungsten is also known as TIG welding and it uses a non-consumable tungsten electrode in the welding process. The tungsten and weld puddle protect and cool with an inert shielding gas, such as argon or helium, and the tungsten electrode heats the objects to form a bond.

What is Soldering?

Soldering is the process by which metals are joined by melting a filler metal into the joint to create strong permanent bonds. Soldering may or may not have capillary attraction and you must do it below a temperature of 840 degrees Fahrenheit. Soldering allows for different types of metals to create a bond, including copper, brass, and gold. Similar to brazing, soldering uses flux to strengthen and improve its mechanical properties.

Soldering methods are grouped according to the method applied. You can use a torch, furnace, induction, dipped, or resistance. Soldering alloys are usually identified by their alloying elements. Soldering might seem similar to welding but it serves different purposes. Solders are typically softer and come in tubes and reels. You use soldering techniques for more electronic devices and in general won’t use welding for the same purposes. Solder bonds are typically not as strong as a brazed or welded bond. However, the key purpose for soldering is to let the two components conduct electricity.

What is Brazing?

Brazing describes the process by which metals are joined using a filler metal into the joint to create strong, permanent bonds. Brazing requires a small joint spacing to allow capillary action to draw the filler metal into the joining when the parts reach the proper phase temperature. Brazing utilizes flux to strengthen and improve its mechanical properties. Fluxes used in brazing have the following major functions:

• Removal of oxides that form as a result of heating.
• Promotion of wetting, the phenomenon of a liquid filler metal or flux spreading and adhering in a thin, continuous layer on a solid base metal.
• Aiding capillary action by pulling the molten alloy into the joint.

Soldering Vs. Welding

The American Welding Society classifies soldering as liquid-solid phase bonding processes. Liquid phase bonding processes entail the filler metal melting and solid phase bonding entails the base material or materials not melting. Soldering does not involve melting the work pieces. The main difference between soldering and welding is the heat source. Soldering is applied using a torch, furnace, or induction and takes place below 840 degrees Fahrenheit. Arc welding uses electricity as a heat source and it reaches temperatures of roughly 10,000 degrees Fahrenheit.

Brazing Vs. Welding

Brazing is also classified by the AWS as liquid-solid phase bonding. Unlike welding, brazing does not involve melting work pieces. Instead, brazing and arc welding use different heat sources, similar to soldering and welding. Brazing also uses a torch, furnace, induction, dipped, or resistance as the heat source and it occurs at 840 degrees Fahrenheit.

Advantages and Disadvantages of Brazing and Soldering

Compared to other methods of joining, brazing and soldering have some advantages. They are as follows:

• Low temperature.
• Permanently or Temporarily joined
• Dissimilar materials can join.
• Speed of joining.
• Less chance of damaging parts.
• Slow heating and cooling.
• Parts of varying thickness can be joined.
• Easy realignment.

Brazing and soldering are processes that come with advantages. However, these advantages are often overlooked when selecting a joining process. The ability to join many different materials with a limited variety of fluxes and fillers reduces material costs for small businesses.

Difference Among Welding, Soldering and Brazing

There are a few differences between welding, soldering, and brazing. Most notably, their heat sources are different and soldering can be completed at lower temperatures than welding. Though they are different, welding, soldering, and brazing can be used for different purposes.