Most TIG welding defects trace back to contamination, poor gas coverage or incorrect consumable preparation. Porosity is caused by contamination entering the weld pool; cracking results from issues such as incorrect filler metal, excessive restraint or rapid cooling; and arc wander is usually down to contaminated or poorly sharpened tungsten, incorrect gas flow or magnetic interference. Clean preparation and good gas protection prevent the majority of problems.
What causes porosity in TIG welding?
Porosity is caused by contamination entering the weld pool. Dirty materials, poor gas coverage, moisture or inadequate shielding gas flow are the most common causes. Clean preparation and good gas protection are essential for producing sound welds. If your gas coverage is suspect, review your set-up in our TIG shielding gas and flow rate guide.
What causes TIG weld cracking?
Cracking can result from incorrect filler metal selection, excessive restraint, rapid cooling or contamination. Some materials, such as aluminium and cast iron, require careful control of heat input and filler metal selection. Following approved welding procedures reduces the risk of cracking. Matching the right filler to the parent material is half the battle — see our TIG filler rod selection guide.
Why does my TIG arc wander?
Arc wander is usually caused by contaminated tungsten, poor sharpening, incorrect gas flow or magnetic interference. Long arc lengths can also reduce arc stability. Maintaining clean consumables and correct machine settings helps produce a focused, stable arc. For correct tungsten preparation, see our TIG tungsten electrode guide.
Prevention starts with the right consumables
Clean materials, correctly prepared tungsten, the right filler rod and good gas coverage prevent the vast majority of TIG defects. Weldability SIF supplies quality TIG consumables to recognised standards, and our team can help you diagnose recurring defects and specify the right products — get in touch. For broader troubleshooting across all processes, see our welding defects and troubleshooting hub.