LME susceptibility of galvanised welded structures of high strength steels

Abstract

Hot dip galvanizing is a very popular and well known process in corrosion protection of steel.However, very occasionally, cracks appear on structures when they leave the zinc bath. The responsiblecrack phenomenon appears to be liquid metal embrittlement. This phenomenon is already known for a longtime, but it is still not yet fully understood. The lack of fundamental theoretical knowledge and the absenceof accurate models to predict liquid metal embrittlement oblige engineers to set up extensive test programsto determine an area of process parameters in which safe design is guaranteed. A qualitativeunderstanding of the various influencing parameters during galvanizing is necessary to explain theoccurrence of liquid metal embrittlement. This knowledge is also helpful to design an experimental test setup and procedure for evaluating the influence of one parameter where the effect of other parameters shouldremain constant. This master thesis deals with the occurrence of liquid metal embrittlement whengalvanizing welded high strength steels. This paper gives an overview of the most important processparameters and gives a short description of possible future experimental work.