A very shallow flux layer may lead to:

• A. Exposure of the arc flashing and possible porosity
• B. Increased penetration
• C. Reduced porosity
• D. Increased bead width

Answer: (A)

Shallow shielding from the flux layer compromises the protective blanket around the molten weld pool. When the flux isn’t thick enough, air can reach the weld area, allowing atmospheric gases to be incorporated into the molten metal as it solidifies. Those gases form porosity, which are unwanted voids in the weld. So the main consequence is the potential for porosity due to inadequate shielding.

The other options don’t align with this effect: increasing heat input or travel slow enough to deepen penetration isn’t caused by a shallow flux layer, and porosity isn’t reduced by having less shielding. Bead width is influenced more by heat input and speed rather than just the depth of the flux blanket.