AG Mechanics CDE Practice Exam 2026 – Comprehensive Test Prep Resource

During the welding process, the layer of oxidized flux that forms on top of the weld bead is called "Dross." When a weld is executed, the flux protects the molten metal from atmospheric contamination by creating a shield over it. As a result of this protection, the flux gathers impurities and forms a layer on top of the weld bead, which is known as dross. It is vital to remove the dross after welding to ensure a clean and solid weld joint.

Options B, C, and D are incorrect:

- Pumice is a type of volcanic rock with a porous texture, commonly used in personal care products like exfoliants.

- Slag is a byproduct of the welding process and is an essential component in creating a shield to protect the molten metal during welding.

- Scoria is a porous volcanic rock used in landscaping and gardening but is not related to the layer of oxidized flux in welding.