Visual Testing (VT) Practice Exam

The term for a rounded discontinuity that occurs in the weld and runs parallel to it is linear porosity. This type of defect is characterized by small voids or gas pockets that form during the welding process. Linear porosity typically appears as a series of small, rounded holes or gaps that align in the direction of the weld bead. It is primarily caused by the entrapment of gas in the molten weld metal, which may not escape during cooling and solidification. Understanding linear porosity is important because it can affect the integrity and strength of the weld joint. If not addressed, these imperfections can lead to undesirable mechanical properties and potential failure of the weldment when subjected to stress or loading. Recognizing linear porosity allows welders and inspectors to determine the quality of the weld and decide on necessary corrective actions or rework to ensure structural reliability.