Porosity in a weld is most often caused by shielding gas issues or contamination such as dirty electrode wire or contaminated base metal. Which of the following is a related factor?

• A. Distortion
• B. Porosity
• C. Penetration
• D. Burn through

Answer: (B)

Porosity occurs when gas gets trapped in molten weld metal, usually because the shielding gas isn’t protecting the weld properly or the metal is contaminated. A related factor here is porosity itself, because it’s the defect you’re dealing with as a result of those shielding or contamination issues. The other terms describe different weld outcomes: distortion is about warping from heat input, penetration is about how deeply the weld fuses into the base metal, and burn-through is about excessive heat cutting through the metal. To minimize porosity, ensure clean base metal and electrode wire, proper shielding gas coverage and flow, and good welding technique to avoid contaminants and gas leaks.