Joint penetration where the weld metal fills the groove and fuses to the base metal through its thickness is called which?

Joint penetration where the weld metal fills the groove and fuses to the base metal through its thickness is called which?

• A. Complete Penetration
• B. Partial Penetration
• C. Incomplete Penetration
• D. Complete Fusion

Answer: (A)

Penetration depth in a weld determines how far the weld metal fuses into the base metal along the joint. When the weld metal fills the groove and fuses to the base metal all the way through the thickness, you have complete penetration. This means the weld reaches the far side of the joint, creating a full-depth weld that provides a continuous load path through the entire thickness. If the weld doesn’t reach the far side, it’s partial or incomplete penetration, leaving part of the thickness unfilled and typically weaker. Complete fusion would involve melting base metal and weld metal together along the joint, but the phrase here specifically describes fusing through the thickness of the joint, which is complete penetration.

Penetration depth in a weld determines how far the weld metal fuses into the base metal along the joint. When the weld metal fills the groove and fuses to the base metal all the way through the thickness, you have complete penetration. This means the weld reaches the far side of the joint, creating a full-depth weld that provides a continuous load path through the entire thickness. If the weld doesn’t reach the far side, it’s partial or incomplete penetration, leaving part of the thickness unfilled and typically weaker. Complete fusion would involve melting base metal and weld metal together along the joint, but the phrase here specifically describes fusing through the thickness of the joint, which is complete penetration.