What is one of the main causes of porosity in welds?

What is one of the main causes of porosity in welds?

• A. Excessive heat during welding
• B. Moisture or contamination in the base metal or filler material
• C. Incorrect welding speed
• D. Poor joint design

Answer: (B)

Porosity in welds is primarily caused by the presence of moisture or contamination in the base metal or filler material. When there are contaminants such as oil, rust, dirt, or moisture on the surfaces being welded or within the filler material itself, these can vaporize during the welding process. As the weld pool solidifies, these vaporized gases get trapped, forming small cavities or pores within the weld. This not only weakens the weld but can also lead to other issues like corrosion susceptibility. Ensuring that surfaces are clean and free of contaminants is crucial for producing high-quality welds and preventing porosity.

Porosity in welds is primarily caused by the presence of moisture or contamination in the base metal or filler material. When there are contaminants such as oil, rust, dirt, or moisture on the surfaces being welded or within the filler material itself, these can vaporize during the welding process. As the weld pool solidifies, these vaporized gases get trapped, forming small cavities or pores within the weld. This not only weakens the weld but can also lead to other issues like corrosion susceptibility. Ensuring that surfaces are clean and free of contaminants is crucial for producing high-quality welds and preventing porosity.