Pulsed TIG Welding Settings: Complete Guide & Charts

What Is Pulsed TIG Welding?

Pulsed TIG (GTAW-P) is a process variation where the welding current alternates between two levels — a high peak amperage and a lower background amperage — at a controlled frequency. Instead of a steady current flowing into the workpiece, the power supply rapidly cycles between these two values, creating a rhythmic heat input pattern.

During the peak phase, current is high enough to establish a weld puddle and achieve fusion. During the background phase, current drops low enough to keep the arc lit but allows the puddle to partially solidify. The result is a series of overlapping spot welds that form a continuous bead.

This is not a gimmick feature. Pulsed TIG is a fundamental technique that solves real problems — particularly on thin materials, heat-sensitive alloys, and out-of-position work where puddle control determines whether you get a good weld or a burned-through mess.

Why Pulse: The Practical Benefits

Reduced overall heat input. The background phase acts as a built-in cool-down between pulses. This means less total energy goes into the workpiece per inch of weld, which directly reduces distortion, warping, and heat-affected zone width.

Better control on thin material. Thin-wall tube and sheet metal are unforgiving. Steady-state TIG at the amperage needed for penetration can melt through before you move the torch far enough. Pulsing lets you hit the material with enough peak current for fusion, then back off before the heat accumulates.

Out-of-position welding. Gravity pulls on the weld puddle constantly. In vertical and overhead positions, a large liquid puddle sags or drips. Pulse keeps the puddle small — each pulse melts a controlled amount of material, and the background phase lets it partially freeze before the next pulse. This is why every orbital welding power supply uses pulsed current as the default operating mode.

Reduced risk of sensitization. On austenitic stainless steels (304, 316, etc.), prolonged exposure to temperatures between 800°F and 1500°F causes chromium carbide precipitation at grain boundaries — sensitization. Lower heat input from pulsed welding reduces time in this critical temperature range.

Controlled bead appearance. Pulse frequency directly controls the bead's visual pattern. At low frequencies (0.5–2 PPS), each pulse creates a visible ripple — the classic "stacked dimes" look. At higher frequencies (5+ PPS), individual pulses blend together and the bead smooths out, approaching the appearance of a steady-state weld.

The Four Pulse Parameters

Every pulsed TIG setup comes down to four variables. Understanding what each one does lets you dial in settings deliberately instead of guessing.

Peak Amperage

The higher current level. This is the current that actually melts the base metal and creates fusion. Set peak amps the way you would set amperage for a conventional (non-pulsed) TIG weld on the same material — or slightly higher, since the peak is only active for part of each cycle.

Effect of increasing peak amps: Deeper penetration per pulse, wider individual puddle spots, more risk of burn-through if other parameters are not adjusted.

Background Amperage

The lower current level between pulses. Its job is to maintain the arc while allowing the puddle to cool and partially solidify. Background is typically set at 25–60% of peak amperage.

Too low: The arc becomes unstable, may extinguish between pulses, and the weld bead gets rough and inconsistent. Below about 5–8 amps, most arcs will not sustain reliably.

Too high: The puddle never partially solidifies between pulses, and you lose the benefits of pulsing. At that point you are effectively running steady-state current with extra noise.

A good starting point is 50% of peak. Adjust down for more cooling effect on heat-sensitive materials, or up if the arc is unstable.

Pulse Frequency (Pulses Per Second / PPS)

How many complete peak-background cycles occur per second. This is the parameter that most visibly affects bead appearance.

• 0.3–1 PPS: Each pulse is clearly visible as a distinct spot. Strong "stacked dimes" pattern. Maximum cooling between pulses. Best for thick or heat-sensitive materials where you want maximum thermal control. Requires the operator (in manual welding) to match travel speed to pulse rate — move one puddle width per pulse.
• 1–3 PPS: The most commonly used range for manual and orbital welding on thin to medium materials. Good balance of thermal control and bead uniformity.
• 5–10 PPS: Individual pulses start blending. The bead looks smoother. Still provides heat input reduction over steady state.
• 50–500 PPS (high-speed pulse): Available on some advanced power supplies. At these frequencies, the bead appears identical to a steady-state weld, but the electrical characteristics improve arc focus and can reduce grain growth. Mostly used in automated and orbital applications.

Peak Time Percentage (Duty Cycle)

The percentage of each pulse cycle spent at peak amperage. At 50%, half the cycle is peak and half is background — equal time at each level. At 30%, peak is active for only 30% of the cycle, and background fills the remaining 70%.

Increasing peak time percentage adds more heat per cycle, wider puddle per pulse, and approaches steady-state behavior at 100%.

Decreasing peak time percentage reduces heat input further, narrows each puddle spot, and increases the cooling ratio.

Most operators start at 40–50% peak time. For heat-sensitive work, dropping to 25–35% provides aggressive thermal management.

Pulsed TIG Settings Chart by Material

These are starting-point ranges. Final settings depend on joint type, material heat, fit-up, and operator technique. All values assume DCEN (straight polarity) unless noted.

Stainless Steel — Thin Wall (0.035"–0.065")

Parameter	Range
Peak Amperage	30–60 A
Background Amperage	15–30 A
Pulse Frequency	1–3 PPS
Peak Time %	35–50%
Tungsten	1/16" or 3/32", 14°–20° included angle
Shielding Gas	Argon, 15–20 CFH

This is the bread-and-butter range for sanitary tube welding and semiconductor tube. Low peak amps, moderate pulse rate, and a sharp tungsten to focus the arc on thin material.

Stainless Steel — Medium Wall (0.065"–0.120")

Parameter	Range
Peak Amperage	60–120 A
Background Amperage	30–60 A
Pulse Frequency	0.5–2 PPS
Peak Time %	40–50%
Tungsten	3/32" or 1/8", 20°–35° included angle
Shielding Gas	Argon, 20–30 CFH

Medium-wall process tube and Schedule 10 pipe. Slower pulse rates work well here — you need longer peak time to fully penetrate thicker material.

Carbon Steel

Parameter	Range
Peak Amperage	50–150 A
Background Amperage	25–75 A
Pulse Frequency	0.5–2 PPS
Peak Time %	40–55%
Tungsten	3/32" or 1/8", 30°–45° included angle
Shielding Gas	Argon or 75/25 Ar/CO2, 20–30 CFH

Carbon steel is more forgiving of heat input than stainless, but pulsing still helps on thin sections and out-of-position work. Background can run a bit higher as a percentage of peak since there is less concern about sensitization.

Aluminum (AC Pulse)

Parameter	Range
Peak Amperage	80–200 A
Background Amperage	40–100 A
Pulse Frequency	0.5–1 PPS
Peak Time %	40–55%
Tungsten	3/32" or 1/8" pure or zirconiated, balled tip
Shielding Gas	Argon, 25–35 CFH

Aluminum pulsed welding uses AC with pulse overlay. The AC frequency controls oxide cleaning, while the pulse frequency controls heat input and puddle size. These are independent parameters on machines that support AC pulse. Not all power supplies offer this — verify your machine has AC pulse capability before programming.

Chromoly (4130)

Parameter	Range
Peak Amperage	40–100 A
Background Amperage	20–50 A
Pulse Frequency	1–3 PPS
Peak Time %	35–50%
Tungsten	1/16" or 3/32", 20°–30° included angle
Shielding Gas	Argon, 15–25 CFH

Chromoly is sensitive to both heat input and cooling rate. Pulsing keeps the HAZ narrow, but avoid excessive cooling between pulses — do not drop background too low, as rapid thermal cycling can cause hardness spikes in the HAZ. Post-weld stress relief may still be required depending on application.

When Not to Pulse

Pulsed TIG is not always the right choice.

Thick plate and heavy pipe (0.250"+). When you need maximum penetration and heat input, pulsing works against you. Steady-state current at high amperage fills the joint faster and maintains the large, fluid puddle needed for multi-pass groove welds. You can pulse for the root pass and cap on thick pipe, but fill passes are often more efficient at steady state.

High-volume production where speed is the priority. Pulse reduces heat input, which means less material melted per second. If the workpiece can handle the heat and distortion is not a concern, steady state is faster.

When your power supply lacks true pulse capability. Some older machines have a "pulse" setting that is really just a slow on-off cycling of the output. If the transition between peak and background is not sharp and controlled, you will not get the benefits of proper pulsed welding — just inconsistent heat input.

Pulse in Orbital Welding

Orbital welding power supplies use pulsed current as a core feature, not an add-on. The orbital weld schedule programs peak and background amperage, pulse frequency, and pulse ratio for each sector around the 360-degree rotation.

Pulse is critical for orbital work because the weld head makes one continuous pass around the tube, transitioning through all positions — flat, vertical, overhead, and back again. Without pulse, the puddle behavior changes drastically at each position. With pulse, the operator programs sector-by-sector adjustments to peak current, background current, and pulse timing to maintain consistent bead geometry all the way around.

In orbital applications, pulse frequencies of 1–3 PPS are most common for tube welding. The frequency is sometimes adjusted by sector — slightly faster in overhead positions for tighter puddle control, slightly slower at the 12 o'clock start where gravity is an ally.

For a detailed walkthrough of sector programming and starter parameters by tube size, see Weld Schedule Programming.

Electrode Prep for Pulsed Welding

Tungsten electrode geometry affects arc behavior under pulsed current. Sharper included angles (14°–25°) generally work better with pulse for two reasons:

1. A sharper taper focuses the arc into a smaller spot, which matches the intent of pulse — concentrated heat during peak, controlled cooling during background. A blunt electrode spreads the arc and can cause the peak pulse to heat a wider area than intended on thin material.

2. Arc re-ignition at the start of each peak phase is more reliable with a sharp, properly ground electrode. A contaminated or mushroomed tip can cause the arc to wander or hesitate as current transitions from background to peak.

Grind tungsten longitudinally (parallel to the electrode axis, not perpendicular) and maintain a consistent included angle. For detailed grinding recommendations by application, see the Tungsten Grinding Angle Chart.

For precision tungsten prep, Shop Tungsten Grinders at TechSouth — handheld and bench models for consistent, repeatable electrode geometry.

Summary

Pulsed TIG is a fundamental process variation, not an advanced trick. The four parameters — peak amperage, background amperage, pulse frequency, and peak time percentage — give you direct control over heat input, puddle size, and bead appearance. Start with the charts above, run test coupons at several frequency and amperage combinations, and document what works for each material and thickness you run regularly.

Related guides: Tungsten Grinding Angle Chart | Weld Schedule Programming | Gas Lens Setup