Why Does Laser Welding Produce Porosity? Causes and Solutions

Porosity is one of the most common welding defects in metal fabrication. Small gas pockets trapped inside the weld can reduce joint strength, affect appearance, and increase the risk of product failure.

Although handheld fiber laser welding machines produce cleaner welds than many traditional welding methods, porosity can still occur if the welding conditions are not properly controlled.

So, what causes porosity, and how can you prevent it?

Dirty Material Surface

One of the main causes of porosity is contamination on the workpiece.

Oil, rust, moisture, paint, or dust can vaporize during welding and become trapped inside the molten pool.

Before welding, always clean the material thoroughly to ensure a stable and high-quality weld.

Incorrect Shielding Gas

Shielding gas protects the molten metal from air during the welding process.

If the gas flow is too low, too high, or unstable, oxygen and moisture may enter the weld pool, increasing the chance of porosity.

Always use the recommended shielding gas and check that the nozzle is clean and properly positioned.

Improper Welding Parameters

Incorrect laser power or welding speed can also lead to porosity.

Low power may not fully melt the material, while excessive speed may prevent gas from escaping before the weld solidifies.

Adjusting the welding parameters according to the material type and thickness is essential for achieving stable weld quality.

Worn Consumables

Damaged consumables can directly affect welding performance.

Regularly inspect parts such as:

• Protective lens
• Welding nozzle
• Wire guide nozzle

Replacing worn components on time helps maintain stable laser output and improves welding consistency.

Choose Reliable Equipment

Stable equipment is just as important as correct operation.

Qingdao Tonchel Industrial Equipment Co., Ltd. manufactures handheld fiber laser welding machines from 800W to 3000W, including air-cooled and water-cooled models for different production requirements.

Tonchel also provides 4-in-1 laser welding machines and offers technical support, welding parameter recommendations, and high-quality consumables to help customers achieve clean, consistent welds with minimal defects.

Conclusion

Porosity is usually caused by contaminated materials, incorrect shielding gas, improper welding parameters, or worn consumables. By maintaining clean workpieces, using suitable settings, and choosing reliable equipment, manufacturers can greatly reduce welding defects and improve overall production quality.

With professional solutions from Qingdao Tonchel Industrial Equipment Co., Ltd., businesses can achieve more stable welding performance and maximize the efficiency of their laser welding operations.