Question

During welding, tiny electrode metal particles are blown out of the arc, which get deposited on the surface of the weld bead and base metal. This weld defect is called

• A. Spatter
• B. Overlapping
• C. Inclusions
• D. Porosity

Hint:

Think of spatter like "grease popping" out of a frying pan. It is molten material that doesn't stay where it is supposed to and ends up as small, hard bumps on the surrounding surface.

Answer 1

The Correct Option is A

1. Defining Spatter:

Spatter consists of small globules or droplets of molten metal that are expelled from the welding arc. These "tiny electrode metal particles" fly through the air and land on the weld bead or the surrounding base metal, where they solidify and stick to the surface.

2. Causes of Spatter: Spatter is generally caused by disturbances in the arc or the molten pool:

• Excessive Current: High amperage can make the arc too violent, blowing metal out of the pool.

• Long Arc Length: Increasing the distance between the electrode and the work makes the arc unstable.

• Magnetic Arc Blow: In DC welding, magnetic fields can cause the arc to wander and "pop," ejecting metal.

• Contaminated Surfaces: Rust, oil, or paint on the base metal can cause gases to expand rapidly, popping molten metal out.

3. Distinguishing from Other Defects:

• Inclusions: Non-metallic materials (like slag) trapped inside the weld metal.

• Porosity: Small gas bubbles or "pinholes" trapped inside the weld as it solidifies.

• Overlapping: When molten weld metal flows over the surface of the base metal without fusing with it at the toe of the weld.