How to Prevent Burning the Copper Nozzle in Laser Welding?

Burning, overheating, and deformation of the copper nozzle are common issues in handheld laser welding. They increase consumable costs and reduce welding stability. Follow these best practices to avoid burning and extend nozzle life.

1. Maintain Correct Working Distance (Critical)

Too close to the workpiece → nozzle exposed to molten spatter & high-temperature plasma → rapid burning

Recommended distance: 8–15mm (8–10mm for thin sheets, 10–15mm for thick plates)

Use guide wheels or fixtures to keep stable height, don't rely on hand stability

2. Keep Protective Lens Clean & Intact

Dirty, cracked, or spotted lens → laser scatters & hits nozzle inner wall → quick burnout

Do:

Inspect the protective lens before every use

Replace immediately if stained, pitted, or burned

Handle only by the edges; avoid touching the glass surface

3. Ensure Laser & Red Dot Alignment

Misaligned laser/red dot → beam hits nozzle wall → instant burn-through

Check: Fire laser into air/ground; ensure spot is centered in nozzle bore and nozzle does not overheat

4. Use Proper Welding Angle

Hold torch at 30°–45° to workpiece

Avoid perpendicular welding (strongest reflection back to nozzle)

For outside corners (more prone to burning), use specialized corner nozzles

5. Shielding Gas: Purity, Flow & Timing

Impure gas (moisture/oil) → micro-explosions at high temp → corrode nozzle

Low flow → poor cooling & anti-spatter; high flow → turbulence & spatter backflow

Standard: Argon purity ≥99.99%; pressure 0.3–0.5 MPa

Start gas before laser; delay gas stop 200ms+ after laser off

6. Match Power & Parameters to Material

Excess power → excessive heat & spatter → nozzle overheats fast

Wobble amplitude ≤3–4mm to avoid angled reflection damage

For aluminum, copper & reflective materials: reduce power & prepare spare nozzles

7. Use High-Quality Nozzles & Replace Timely

Choose high-purity copper (ETP copper) nozzles (better thermal conductivity & heat resistance)

Replace at first sign: discoloration, deformation, spatter buildup

Regularly clean spatter & oxidation from nozzle surface