In welding terminology, which term describes gas bubbles trapped in the weld?

In welding terminology, which term describes gas bubbles trapped in the weld?

• A. Porosity
• B. Penetration
• C. Fusion
• D. Slag

Answer: (A)

Porosity is the term for gas bubbles trapped in the weld. It happens when shielding gas fails to fully protect the molten weld pool, or when contamination such as oil, rust, or moisture is present, or when improper welding parameters create turbulence that traps gas as the metal solidifies. These voids can be spherical or irregular and weaken the weld, potentially causing leakage or reduced strength. Prevention involves ensuring stable shielding gas coverage, keeping materials and electrodes clean and dry, using proper amperage and travel speed, and controlling technique to minimize turbulence. Porosity is different from penetration (how deeply the weld fuses into the base metal), fusion (the melting and joining of base metals), and slag (the solidified impurity layer on some welds).

Porosity is the term for gas bubbles trapped in the weld. It happens when shielding gas fails to fully protect the molten weld pool, or when contamination such as oil, rust, or moisture is present, or when improper welding parameters create turbulence that traps gas as the metal solidifies. These voids can be spherical or irregular and weaken the weld, potentially causing leakage or reduced strength. Prevention involves ensuring stable shielding gas coverage, keeping materials and electrodes clean and dry, using proper amperage and travel speed, and controlling technique to minimize turbulence. Porosity is different from penetration (how deeply the weld fuses into the base metal), fusion (the melting and joining of base metals), and slag (the solidified impurity layer on some welds).