Problems with reliability and safety of hot dip galvanized steel structures

摘要: Hot dip galvanizing is very effective means of protection against corrosion. Some recommendation concerning the steel quality are generally known and accepted. The process consists cleaning (pickling or sand blasting) dipping structures pieces into liquid zinc bath. case study hot galvanized steels presented. recent failures welded high strength screws Structures were made S355 grade MIG/MAG was applied for welding. Large cracks observed in vicinity welds after process. presence both hydrogen metal embrittlement identified associated mainly with higher hardness HAZ quenched tempered steels. Possible cracking mechanisms discussed. influence chemical composition production (welding, heat treatment) analyzed according to data published literature. solutions recommendations avoiding failure proposed.