Characterization of cold lap defects in tandem arc welding
Journal article, 2012

The objective of this investigation was to classify and characterize the small lack of fusion defects, called cold lap, located at the weld toe. Since the defects are very small (0.01–1.5 mm) and diffi cult to detect by NDT methods, a better understanding of the formation mechanism is required to be able to avoid their formation. The investigation consisted of two parts. Firstly, a study was made on the type and frequency of cold laps. Three types were identified, namely “spatter cold lap”, and “overlap cold lap” and “spatter-overlap cold lap”. No relation between type or frequency of cold laps and the welding parameters could be established. Secondly, the interface between spatter and the base material was investigated using optical and scanning electron microscopy, to better understand the cold lap formation mechanism. Manganese-silicate particles were found in the interface located in such a way that they may assist cold lap formation.


MAG welding

Lack of fusion

Wire feed

Tandem welding

Arc welding


Lars-Erik Svensson

Per Nylén

Uta Klement

Chalmers, Materials and Manufacturing Technology, Surface and Microstructure Engineering

Welding in the World, Le Soudage Dans Le Monde

0043-2288 (ISSN)

Vol. 56 9-10 20-25

Subject Categories

Materials Engineering

Areas of Advance


Materials Science



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