AC vs DC arc welding are two types of arc welding that create an electric arc using various currents. An electric arc is created between an electrode and the metal being welded in several forms of welding. The heat from the electric arc is used to fuse the metals. If you still don’t know what is the difference between AC and DC Arc welding, here is a comprehensive guide for you. Let’s begin!
The arc is generated by a power supply, which can be either alternating current (AC) or direct current (DC) (DC). The polarity of the electrical current that passes through the electrode is determined by the power source (AC or DC). Therefore, the weld generated is also influenced by the power source utilized. The strength and quality of your weld are influenced by the electrode polarity you choose.

The two types of current flow are also known as ‘electrode negative’ and ‘electrode positive.’ In addition, they are commonly referred to as ‘straight’ or ‘reverse.’ The DC polarity remains constant. Still, the AC polarity alternates between flowing in one direction for half of the time and in the opposite, reverse direction for the other half of the time.
Major Differences of AC & DC Welding
The following are the key distinctions between ac and dc welding. Let’s have a look on them.
Size | AC Welding equipment is smaller than the DC Welding equipment. |
Weight | Most DC welding equipment are heavier than AC welders. |
Arc Blast | AC welding machines are simple to operate than DC welders. |
Voltage | AC welding has smaller voltage drop, also allows it to operate from a distance than DC. |
Cost | AC welding machines are more pricey than DC |
Applications of AC Arc Welding
To under the AC Arc welding more deeply, we are quoting some significant AC Arc welding:
Small-scale Household Applications
Many of the small AC welders of the buzz-box design will function with household current. So you won’t need to hire an electrician to get these entry-level welders set up. However, if you’re just getting started or need a portable welder to travel to a friend’s shop, AC is the way to go.
You can also read: Welding History
Heavy Machinery
Different components of heavy machinery might get magnetized, necessitating the use of AC welders. Working on rusted or filthy equipment is also a little simpler with AC stick welders than with other procedures. Stick welders are also simpler to operate with the outside than other varieties, making them ideal for AC equipment.
Aluminum TIG Welding
Alternating current’s rapid polarity reversals provide a cleaning effect on metal. The oxide layer is prevented from contaminating the weld bead and weakening the connection in this way. AC settings for aluminum are tuned in high-quality TIG welders (TIG welders for Aluminum). Make sure you obtain an AC/DC TIG welder if you wish to TIG weld metal.
Applications of DC Arc Welding
Same as AC welding, DC Arc welding also have some important applications such as:
Welding from Above (Odd Angle)
When operating overhead, the added spatter from AC welding becomes a greater issue. This is because you receive spatter on yourself and your work environment instead of splatter on the welded component. The direct current keeps things cleaner and safer by reducing splatter. Therefore, stick with the direct current if you perform a lot of overhead work.
Thinner Metal Welding
DC welds allow you to work a little faster, which is ideal for thin metal. When working with thin stock, moving too slowly might cause the metal to burn through, resulting in further difficulties. Welding sheet metal requires a lot of speed. Anything that slows you down might cause you to burn through your material — for sheet metal, utilize DC.
FAQs
Wrapping Up
In short, both AC and DC arc welding have their own significance and applications. We cannot pass any statement that which one is good or bad. Further, there are a lot of differences in both but we have mentioned only those which are the basic and important for you to know about them. If you want to add something here or have any confusion, feel free to interact with us using comments.
Happy Welding!
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