Formation of lack of fusion defects and hot cracks in welding steel structures with a corrosion-resisting zinc coating

Abstract

The conditions of formation of lack of fusion defects and hot cracks in welded joints in welding steel structures with zinc coatings are investigated. The results show that the probability of formation of lack of fusion defects in the metal of the welded joints produced in CO₂ mechanized welding with a consumable electrode increases with increase of the thickness of the zinc coating and is caused by the additional consumption of the heat of the welding arc for evaporation of zinc. To prevent the formation of lack of fusion defects in the metal of these welded joints, it is recommended to correct the welding conditions taking the thickness of the zinc coating into account.

Keywords:

• Welding
• welding wire
• welding deposit
• pores
• faulty fusions
• calorimetry
• arc
• coating

Notes

Selected from Svarochnoe Proizvodstvo, 2015, 68 (12) 13–16.