The type and quality of welding are defined by the kind of current used by the welder. Using the suitable current type is essential to get your desired welding results. Universally, there are two types of currents; direct current and alternating current, generally known as DC and AC.
So, do MIG welders use direct currents or alternating currents? The answer is simple. MIG welders use direct current (DC) for most welding applications, ensuring an unhindered welding process. The reason is that direct current does not comprise alternating polarities, thus carrying each separately to achieve the required results.
Keep reading below to know more about why Dc is preferred over AC in MIG welding.
Why do MIG welders prefer DC more than AC?
MIG welders prefer direct current (DC) over AC because of the current’s stable, single-direction flow. Whereas, if AC is used, it will change its flow multiple times, almost 120 times in a minute, not giving the required results. This means that a frequent flow change can affect the smoothness of the process, including other changes le the stability of the arc or its penetration. Therefore, dc MIG welding offers a smoother and seamless application compared to alternating current.
Also, watch this video to understand AC vs. DC welders in detail:
What are the advantages of DC MIG welding?
There are numerous advantages of using DC in MIG welding than AC. Here are a few:
- Less spatter: Since the current flows in a single direction only, the DC MIG welding offers a hinder-free process, keeping the spatter of the weld at bay with no post-weld cleanup required.
- High Quality Results: DC ensures the stability of the arc, which has a direct effect on the quality of the weld. This is the main reason DC MIG welders are in colossal demand compared to AC MIG welding.
- Suitable For Welding Thin Metals: MIG welders using direct current prove to be an excellent choice for welding thin metals. This is because a controlled arc does not penetrate beyond a specific limit, allowing the welder to regulate the process according to his requirements.
Is Alternating Current Used In MIG Welding?
Unlike DC, alternating current does not have to offer much on its plate; still, its use cannot be ruled out entirely. A few circumstances can persuade you to prefer AC MIG welding over DC welding. For example:
- Low Budget: Despite AC welding machines causing a lot of difficulties, many professionals prefer AC over DC because they are very affordable in price.
- Welding Non-Ferrous Metals: If a DC MIG welding machine is used in non-ferrous metals, it can form an oxide layer on the top that directly reacts with the direct current. However, this issue does not arise in AC machines.
What are some pros and cons of AC welding?
Here are some of the pros and cons of AC welding machines listed below.
Pros.
- Can weld magnetic and thick metals
- Affordable.
- Better penetration.
- Best for welding at high temperatures.
Cons.
- Compromised weld quality.
- Unsmooth welding process.
- Noticeable welding spatter.
- Low arc stability.
End Note
The purpose of this article was to elaborate on all relevant details related to the question posed in the first place. It is evident that DC MIG welding has many advantages over AC, mainly due to its freedom to the welder. Therefore, DC is the go-to choice for most welding applications due to the same reason.
