TIG Pulsed Welding And When To Use It

TIG, or Gas Tungsten Arc Welding, is a popular method for joining thin and delicate metal pieces. Its key advantages include excellent heat control, precision, and weld quality.

Today, welders often use pulsed TIG welding to improve heat control even further. Pulsing involves oscillating between peak and background amps to reduce overall heat buildup and promote cooling without extinguishing the arc.

In this article, we'll explain TIG pulsed welding and when to use it to get the most out of this fantastic technique. So, without further ado, let's explore pulsed TIG and its applications.

Pulsed TIG Welding on Aluminum
Source: https://www.youtube.com/watch?v=dpQ22DdN11E

What Is Pulsed TIG Welding?

In TIG pulsed welding, the current cycles between a high (primary amps) and a low value (background amps) at the given frequency (Hz). Instead of supplying a consistent current output, the welder pulses between the high and low amps to reduce the overall heat input.

How Pulsed TIG Welding Works
Source: https://www.youtube.com/watch?v=YcIiDU3UF8Q

At high amps, the arc melts the base metal and filler rod, providing proper penetration. At low amps, it promotes cooling and reduces heat buildup, which is crucial when welding thin, heat-sensitive, and delicate metals.

Due to its excellent heat control, pulsed TIG welding became a must-have when TIG welding thin metal sheets. Additionally, welders prefer pulsing when welding metals with relatively low heat conductivity, such as stainless steel and high-tech nickel alloys like Inconel and Hastelloy.

If you are an older welder, pulsed TIG may seem similar to pumping the foot pedal. However, today, the entire process is fully automated to provide consistent pulsing rates, with up to 200 or more switches per second.

Pulsed TIG Welding on a Stainless Steel Tube Using the YesWelder TIG-200P-ACDC-PRO
Source: https://www.youtube.com/watch?v=v_-gcvI1eLg

Pros and Cons of TIG Pulsed Welding

Due to the very nature of pulsed TIG welding, it yields a lot of advantages that many welders enjoy. The most significant advantages of pulsed TIG welding involve the following:

• It provides excellent heat control

• Improves penetration and travel speed

• Improved weld aesthetics and weld quality

• It is excellent for out-of-position welding

• Great for welding near edges and holes

Advantages of Pulsed TIG Welding

There are only so many cons of pulsed TIG welding. But some notable ones we could mention are:

• Mastering the technique takes time: Pulsed TIG is not a beginner-friendly method, as it takes some time to experiment and get everything straight.

• Equipment expenses: Pulsed TIG welders can be more expensive and complex than regular welders, so we strongly recommend checking out YesWelder TIG machines that will keep your bank intact.

TIG Pulsed Welding Parameters

If you have a pulsed TIG welder, such as YesWelder TIG-205P-Pro , but want to make the most of it, you must first understand the fundamental pulsed TIG parameters. The main TIG pulsed welder settings include:

TIG-205P-PRO Pulse TIG Welder

• Primary amperage (High amps)

• Background amps (Low amps)

• Frequency (Pulse per second)

• Pulse width (Pulse on time)

With these four variables, you can make hundreds of configurations. So, if you are a beginner, you are probably wondering where to start. The values largely depend on the material type, thickness, travel speed, welding position, and welding technique. However, there are some tips you need to know before experimenting with pulsed TIG.

High Speed Pulse TIG for Edge Welding
Source: https://www.youtube.com/watch?v=SAliiVzU71A

Peak Amperage (Main Amperage)

Peak amps, primary or main amperage, is the upper limit of the pulsing cycle. These are the maximum amps the current will reach when pulsing. Simply put, this is the amperage you would set on a constant power source.

However, be cautious when setting the max amps in pulsed TIG. Since the current oscillates between high and low values, the overall output amperage is roughly the average of the high and the low amps. Thus, you should always increase the peak amperage for the given metal thickness.

For example, TIG welding 1/16" mild steel requires approximately 60-75 amps, depending on your technique and power source. If you switch to pulsed TIG, you should use at least 100 amps peak or even double the amperage to get enough heat into the joint.

TIG Pulsed Welding Stainless Steel
Photo by @dylan.borbely (TikTok)

Background Amperage

The background amps represent the lower end of the cycle or the low amps the current oscillates to. Depending on the TIG welder, you can set this parameter in exact amps or a percentage of primary amps. Either way, this parameter is pretty straightforward, but it can significantly impact welding results.

Setting the exact background amperage is simple and suitable for experienced welders who like to fine-tune their TIG welders. However, the background amps are more commonly expressed as a percentage of the primary current. For example, if your primary amps are 100 A and you set the background amps at 25%, the current will cycle between 100 and 25 amps.

As a new welder, you should keep the background amperage approximately 20-50%. In general, 25% to 40% background current with a higher primary current will give you a more fluid puddle and faster travel speeds.

Keeping the background current below 20-25% will significantly lower the overall amperage output, so you should avoid it. Conversely, maintaining a background current over 50-60% greatly increases the heat input, so you negate the effects of pulsing.

Pulsed TIG Welding Stainless Steel at 85 Amps and 1 PPS
Photo by @dylan.borbely (TikTok)

TIG Pulse Frequency

The pulse frequency denotes how many times in one second the current cycles between high and low amps. It is expressed in Hertz (Hz) and basically defines the number of pulses per second (PPS). The frequency can have different effects on the arc and weld; here is how.

Source: https://weldingpros.net/pulse-tig-welding/

• Very low frequency (1 Hz): With 1 Hz frequency, you get a single pulse per second, which can be highly beneficial in catching the move and dab rhythm. Like a musician with a metronome, you dab the rod during high amps and remove it during low amps. This frequency produces the "stacked dimes" weld appearance many are looking for from TIG welds and, overall, excellent weld aesthetics.

• Low frequency (2-10 Hz): A low frequency of 2-10 Hz produces a soft arc. The weld bead is broad, but the penetration is low. As a result, you can use it to weld an outside corner joint or cap pas in multi-pass welding, where penetration is not paramount.

• Strobe frequency (10-30 Hz): A pulse frequency between 10-30 Hz produces a specific strobe condition that many find unsettling. Although you can experiment in this range, you may find it disorienting, so we recommend using it only for a short time.

• Default frequency (100 Hz): Most TIG welders have a default frequency set at 100 Hz, which is a great starting point for most beginners. Default frequency offers a sweet spot for most welding projects that involve pulsed TIG, so we recommend starting with it and then working on your preferences.

• High frequency (over 100 Hz): Frequencies over 100 Hz produce a stiff arc, creating narrow, deep-penetrating welds. These are ideal for narrow joints that need more penetration, and they yield faster travel speed and better arc control. Industrial-grade welders offer frequencies up to 500 Hz.

Influence of Pulse Frequency on Pulsed TIG Behavior
Source: https://www.researchgate.net

TIG Pulse Width

Pulse width, or pulse-on-time, represents the time the current spends in the upper cycle of the pulse. By default, this value is set to 50%, which means the current spends an equal amount of time in peak and background amps. However, advanced TIG welders allow you to tweak this option.

TIG Pulse Width Explained

For new and beginner welders, a pulse width of 40-60% is a sweet spot for most welding projects. By reducing the width below 50 percent, the current spends more time in low amps, meaning it reduces the heat exposure. Lower width is ideal when TIG welding thin sheet metal, but you shouldn't go below 30%, as it will limit the heat too much.

Pulsed TIG Welding Applications - When and Why To Use TIG Pulsing

All the advantages of TIG pulsed welding make it an obvious and go-to choice in various applications. These applications most commonly involve the following:

• Welding thin sheet metal

• Welding delicate, heat-sensitive metals

• Out-of-position welding

• Welding outside corners, edges, and holes

• Producing excellent weld aesthetics

• Improving welding speed and penetration

Let's further explain why.

Pulsed TIG Welding Applications
Source: https://www.youtube.com/@weldingtipsandtricks/

Pulsed TIG Welding on Thin Sheets

Welding thin sheet metal can be a nightmare, as even the slightest mistakes can cause burn-through, warping, or distortion. Excessive heat is the leading cause of most defects on thin gauges, so many welders turn to TIG welding and its low amps.

Pulsed TIG provides even better heat control, making it ideal for welding thin sheets down to 20 or even 22 ga. Overall, pulsed TIG is excellent for welding any thin metal.

Peak amps provide enough penetration, while background amps prevent excessive heat buildup. As a result, TIG pulsing offers just the right amount of heat to achieve proper penetration and avoid issues such as distortion or warping. It also prevents unnecessary filler metal buildup, which can, yet again, cause distortion or warping.

Pulsed TIG Welding on Thin Metal
Source: https://www.youtube.com/watch?v=dpQ22DdN11E

Welding Delicate Metals with Pulsed TIG

Pulsed TIG welding is ideal for delicate and heat-sensitive metals such as stainless steel or high-tech nickel alloys. Stainless steel has low thermal conductivity, which creates excessive heat exposure to the Heat-Affected Zone (HAZ).

Localized heating and cooling cause distortion, so it's no wonder many say that even if you look at the stainless steel wrong, it will distort. All jokes aside, improving the heat won't help, but better heat control will.

When we mention heat control, pulsed TIG is the first thing that comes to mind. This technique provides the perfect solution, as it minimizes the heat input while creating good fusion and optimizing the bead profile. Additionally, pulsed TIG reduces the filler metal deposition, as excessive rod buildup can promote distortion in the weld bead.

Pulsed TIG Welding Aluminum
Source: https://www.youtube.com/shorts/sewFLh_iL6c

Out-of-Position Welding with Pulsed TIG

Welding in vertical or overhead positions can be highly challenging, even for seasoned welders. Gravity pulls the molten puddle from the joint, and the molten metal can end up on your helmet or leak down the joint. The higher the weld pool fluidity, the higher the risk of the weld fleeing the joint.

There are various ways to solve this issue, but a simple one is using a pulsed TIG. By reducing the pulse width or peak pulse time, you can reduce the puddle fluidity while retaining enough penetration. Additionally, you can increase the pulsing to get a stiffer arc but lower the puddle fluidity.

TIG pulsed welding is also excellent when welding in tight spaces. Pulsing helps minimize the torch movement, which is often limited when welding in cramped weld joints. With a steady hand on the torch, you can control the filler metal distribution, which is crucial in these challenging situations. With a smaller torch and enough dexterity, pulsed TIG is ideal for cramped positions.

Vertical-Up Pulsed TIG Welding Process
Photo by @nick.sciacca (TikTok)

Improved Weld Quality and Aesthetics with Pulsed TIG

Many welders prefer TIG welding due to its ability to produce the highest-quality, clean, and visually appealing welds. However, you can improve aesthetics further by using pulsed TIG.

As noted, low pulse settings, such as 1 Hz, allow for the production of the "dime-on-dime" welds that many are looking for. Stacked dimes are a TIG welding special that many consider a hallmark of a beautiful TIG weld. Additionally, welders often use low-frequency pulsed TIG to repair an uneven bead profile. Even pulsing can add a regular ripple pattern that wasn't there previously.

This ripple effect, also referred to as weld agitation, sometimes benefits the joint. By reducing the surface tension, it helps prevent contaminants from getting stuck underneath the weld and fills the joint more evenly. So, besides the appearance and aesthetics, pulsed welding can also improve the overall quality of TIG welds.

Clean, High-Quality Pulsed TIG Welds
Photo by @cefosol_osona (TikTok)

Welding Outside Corners, Edges, and Holes with Pulsed TIG

The perfect heat control of pulsed TIG welding can help you weld around edges and holes, which is considered highly challenging. High heat often causes edges to burn up or distort. Excessive heat near holes causes them to expand, and excessive filler metal can fill them.

Pulsed TIG and its excellent heat control allow you to make a quick, clean weld without ruining an edge or filling a hole. Simply put, pulsed TIG provides extra control and accuracy in a difficult welding position.

Additionally, you can use low-frequency pulsed TIG to weld outside corners or a cap pass. As noted, a low frequency of 2-10 Hz produces a soft arc and broad, shallow penetration weld bead. This type of weld bead is ideal when welding outside corner joints, as you don't need too much penetration. Additionally, the broad weld is a good choice to cap the multi-pass welds and root passes.

Pulse TIG Welding Outside Corners
Photo by @overkillracingandchassis (TikTok)

Improving Weld Speed and Penetration with Pulsed TIG

TIG welding is considered one of the slowest welding methods, and drawbacks are often notable in large-scale applications. However, bumping up the frequency can help you increase the weld speed and finish the projects much faster, but it takes a lot of time to get used.

Welding at rates over 100 or 150 Hz can be challenging for beginners. Tuning up the PPS increases the weld pool fluidity, allowing you to fill the joints quickly. However, highly fluid puddles can be very difficult to control for inexperienced welders, so many stick to defaults or lower frequencies.

In addition to speed, high frequency creates narrow, deep, penetrating welds. These are ideal for welding thicker metal or increasing productivity on repetitive welds.

Pulsed TIG Welding 20-Gauge to Schedule 10 Stainless
Photo by @rangerjoe1989 (TikTok)

Pulsed TIG in Industrial Applications

Precision, cleanliness, heat control, and enhanced weld quality are some of the key advantages that make pulsed TIG a highly valuable part of industries worldwide. TIG pulsed welding is reserved for more complex and advanced industries, including the following:

• Aerospace industry: Welders in the aerospace industry use pulsed TIG to weld thin materials, intricate components, and exotic alloys like titanium, Inconel, and aluminum. Heat control, weld quality, and precision are critical to maintaining the structural integrity of aerospace components.

• Automotive industry: Welders use TIG pulsed welding to weld thin-gauge stainless steel and aluminum components, exhaust systems, and high-performance parts in the automotive industry. Once again, the heat control allows them to join thin and heat-sensitive parts.

Pulsed TIG Welding Stainless Steel Exhaust
Photo by @kullyco (TikTok)

• Medical equipment manufacturing: Pulsed TIG is highly useful when welding surgical tools, implants, and cleanroom equipment. High weld quality, precision, and cleanliness are paramount in medical equipment production.

• Electronics: TIG pulsed welding is valuable when welding small, intricate parts such as connectors, sensors, and circuits. Arc control prevents overheating of delicate components.

• Food and beverage: Welders use pulsed TIG to weld stainless steel tanks, piping, and other food processing components. Welds must be smooth and clean to avoid contamination and maintain hygienic conditions.

Pulsed TIG Welding Food Grade Tubing
Photo by @invertedfabrication (TikTok)

• Nuclear industry: Pulsed TIG joins critical components like piping, heat exchangers, and pressure vessels in the nuclear and energy sectors. Welding exotic and high-strength alloys with minimal defect rates is crucial.

• Metal art and sculptures: Pulsed TIG's weld aesthetics are ideal for sculptures, railings, and decorative structures made of metals like stainless steel and aluminum.

TIG Pulsed Welding Metal Art
Source: https://www.youtube.com/watch?v=71MKgTX638g&t=652s

Final Thoughts

Pulsed TIG welding is a fantastic technique that improves the already astonishing TIG welding by providing even better heat control, weld aesthetics, and speed. The ability to cycle between high and low amperage makes TIG pulsing highly useful in various situations and applications.

Welders most commonly use this technique when welding thin, exotic, or heat-sensitive metals. By tweaking the settings, welders can use it to TIG weld overhead, vertically, or in cramped positions. Its heat control can improve weld quality and aesthetics.

These advantages are also highly valuable in industrial applications, in addition to home projects. Pulsed TIG welding is commonly used in advanced industries such as aerospace, automotive, nuclear, electronic, and food and beverage.

Pulsed TIG Welding Process
Photo by @rangerjoe1989 (TikTok)

🧐 TIG Pulsed Welding And When To Use It FAQ

1. What are the key advantages of TIG pulsed welding?

It provides excellent heat control, improves penetration and travel speed, enhances weld aesthetics and quality, is suitable for out-of-position welding, and works well for welding near edges and holes.

2. What does pulse frequency do?