What are the most important laser welding parameters?

For thin-sheet laser welding the key parameters are peak power, wire diameter and feed rate, wobble scan width, wobble frequency, shielding gas flow and focus position. Together they control penetration depth, bead width, porosity and heat input.

Which peak power should I use for stainless steel between 0.8 and 3.0 mm?

For handheld fiber laser welding on stainless steel 0.8–3.0 mm, typical peak power settings are 30–40% for 0.8–1.2 mm, 40–50% for 1.5–2.0 mm and 65% for around 3.0 mm when using a 1200 W source and appropriate wobble and wire feed settings.

How should the focus be set for aluminium laser welding?

For aluminium sheet the focus is usually shifted above the surface by about +3 to +5 mm. Together with high nitrogen flow this helps reduce soot and porosity while maintaining a stable molten pool.

When should I choose 800 W vs 1200 W for handheld laser welding?

800 W handheld fiber welding is best for 0.5–2.5 mm stainless and carbon steel where heat input must be very low. 1200 W is recommended when you regularly weld 2–4 mm carbon steel, 3 mm stainless or 1–2 mm aluminium because it provides more penetration reserve and higher speed.

Laser Welding Parameters for Stainless Steel, Carbon Steel and Aluminum (0.5–4 mm)

Laser welding parameters decide whether a weld is strong, stable and repeatable in production. This guide summarises the key settings for handheld fiber laser welding using real 800 W and 1200 W data on stainless steel, carbon steel and aluminium from GWEIKE M-Series 6-in-1 systems.

What you will find in this guide

Explanation of peak power, wire feed, wobble scan width, frequency, gas flow and focus position
Recommended parameter windows for 0.5–4 mm stainless and carbon steel, and 1–2 mm aluminium
Practical optimisation tips for thin-sheet production lines

Core Laser Welding Parameters (Explained)

Peak Power (%)

Peak power controls penetration depth and the size of the molten pool. On the M-Series 1200 W handheld system, typical peak power settings for thin sheet are:

Stainless steel 0.5–1.0 mm: 23–38 %
Stainless steel 1.2–1.5 mm: 40–45 %
Stainless steel 2.0–3.0 mm: 45–65 %
Carbon steel 2.0–4.0 mm: 67–95 %
Aluminium 1.0–2.0 mm: 50–85 %

Higher peak power increases penetration but also raises heat input. For thin visible parts, it is usually better to start at the lower end of the window and increase gradually until full fusion is reached.

Wire Diameter and Feed Rate

Wire is used to fill gaps, increase bead width and improve joint strength. From our welding table:

0.8 mm stainless uses 0.8 mm wire at 18 mm/s (30 % peak power).
1.5 mm stainless uses 1.2 mm wire at 13 mm/s (40 % peak power).
3.0 mm stainless uses 1.2 mm wire at 8 mm/s (65 % peak power).
3.0–4.0 mm carbon steel uses 1.6 mm wire at 6–8 mm/s (85–95 % peak power).
2.0 mm aluminium uses 1.6 mm wire at 10 mm/s (85 % peak power).

As a rule of thumb, thicker plates require larger wire diameters and lower feed rates to maintain a stable pool.

Wobble Scan Width (mm)

Wobble scan width defines the lateral movement of the beam and directly affects bead width and heat distribution. The M-Series test data uses:

Thin sheet (0.5–1.0 mm): 1.5–2.5 mm scan width
1.2–2.0 mm sheet: 3.0–3.5 mm scan width
3.0–4.0 mm sheet: 4.0–4.5 mm scan width

Increasing scan width helps avoid burn-through on very thin materials and improves tolerance to joint fit-up variations.

Wobble Frequency (Hz)

Wobble frequency (scanning frequency) influences bead smoothness and agitation of the molten pool:

0.5 mm stainless: up to 150 Hz for very smooth beads.
0.8–1.5 mm stainless and carbon steel: typically 60–100 Hz.
2.0–4.0 mm sheet: 25–40 Hz to keep energy concentrated.

Shielding Gas and Flow Rate

All tests use nitrogen shielding with a flow of ≥20 L/min. If the flow is too low, oxidation and porosity will increase. Excessively high flow may disturb the molten pool. For aluminium and stainless steel, maintaining a stable, laminar gas flow is critical for bright, clean welds.

Focus Position

Focus position changes how the beam energy is distributed along the thickness:

Stainless and carbon steel: focus at the surface (0 mm) for most butt and fillet welds.
Aluminium: focus shifted +3 to +5 mm above the surface to reduce soot and porosity.

Correct focus is especially important when welding reflective materials or when you want to minimise top-side spatter.

Recommended Parameter Windows (1200 W)

The following tables summarise representative 1200 W handheld welding parameters for thin sheet. Values are indicative starting points and should be fine-tuned for each material batch and joint design.

Stainless Steel (0.5–4.0 mm)

Thickness (mm)	Wire Ø (mm)	Wire Feed (mm/s)	Peak Power (%)	Scan Width (mm)	Frequency (Hz)	Typical Use
0.5	—	—	23	1.5	150	Micro lap welds, thin covers
0.8	0.8	18	30	2.5	100	General thin sheet, visible seams
1.0	0.8	18	38	2.5	100	Cabinet panels, brackets
1.2	1.0	15	40	3.0	100	Frame and enclosure welding
1.5	1.2	13	40	3.0	60	Corner joints on boxes and doors
2.0	1.2	12	45	3.5	40	Reinforced brackets, stiffeners
2.5	1.2	10	50	3.5	40	Heavier frames and posts
3.0	1.2	8	65	4.5	30	Load-bearing joints on 3 mm sheet
4.0	1.2	6	75	4.5	25	Near maximum thickness for handheld

Carbon Steel (0.5–4.0 mm)

Thickness (mm)	Wire Ø (mm)	Wire Feed (mm/s)	Peak Power (%)	Scan Width (mm)	Frequency (Hz)
0.5	—	—	23	1.5	150
0.8	0.8	18	33	2.5	100
1.0	0.8	18	38	2.5	100
1.2	1.0–1.2	15	38	3.0	100
1.5	1.2	12	40	3.0	100
2.0	1.2	12	67	3.5	30
2.5	1.2	10	70	4.0	30
3.0	1.6	8	85	4.5	30
4.0	1.6	6	95	4.5	25

Aluminium (1.0–2.0 mm)

Aluminium has high thermal conductivity and reflectivity. Correct focus and gas flow are essential.

Thickness (mm)	Wire Ø (mm)	Wire Feed (mm/s)	Peak Power (%)	Scan Width (mm)	Focus (mm)	Frequency (Hz)
1.0	1.0	15	50	2.5	+3	100
1.2	1.0–1.2	13	55	2.5–3.0	+3	80
1.5	1.2	12	70	3.0	+3	40
2.0	1.6	10	85	4.0	+5	40

For all aluminium tests, nitrogen flow was maintained at ≥20 L/min. In many cases 25–30 L/min further improves protection and reduces soot.

How Parameters Influence Weld Quality

Penetration Depth

Penetration increases when:

Peak power is increased
Scan width is reduced
Travel speed or wire feed is reduced

On 3 mm carbon steel, for example, moving from 70 % to 85 % peak power with a 4.5 mm wobble width is often the difference between partial and full penetration.

Bead Width & Appearance

Bead width grows when:

Wobble scan width is increased
Wire diameter and feed are increased
Frequency is adjusted for a smoother oscillation

For cosmetic stainless seams on 1.0–1.5 mm sheet, many users prefer 3.0 mm wobble with 60–100 Hz to obtain a wide, bright seam with very low spatter.

Example Parameter Sets

1.5 mm Stainless Steel – Visible Corner Seam

Laser power: 1200 W
Wire: 1.2 mm, 13 mm/s
Peak power: 40 %
Scan width: 3.0 mm at 60–100 Hz
Gas: nitrogen ≥20 L/min, focus at surface

This setting produces a smooth, low-distortion corner weld suitable for doors and cabinets. Grinding can often be eliminated, saving significant finishing time compared to TIG.

2.0 mm Carbon Steel – Structural Fillet

Laser power: 1200 W
Wire: 1.2 mm, 12 mm/s
Peak power: 67 %
Scan width: 3.5 mm at 30 Hz
Gas: nitrogen ≥20 L/min

Compared with MIG, this parameter window offers similar or higher strength with less spatter and a much smaller HAZ, reducing distortion on long fillet welds.

2.0 mm Aluminium – Housing and Frame Parts

Laser power: 1200 W
Wire: 1.6 mm, 10 mm/s
Peak power: 85 %
Scan width: 4.0 mm at 40 Hz
Focus: +5 mm above surface, nitrogen ≥25 L/min

With correct focus and gas flow, aluminium welds show reduced soot and porosity compared with conventional TIG, especially on long continuous seams.

Need a Parameter Window for Your Parts?

Share your drawings, material grades and current MIG/TIG settings. GWEIKE application engineers will recommend a fibre laser welding window based on the 800–1200 W data above and run sample welds on your material.

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