An evaluation of steels subjected to rock bolt SCC conditions

In order to understand the metallurgical influences on rock bolt stress corrosion cracking (SCC), an evaluation has been carried out of a range of steels subjected to the conditions previously identified as producing laboratory SCC similar to that observed for rock bolts in service. The approach has been to use the linearly increasing stress test for samples exposed to a dilute pH 2.1-sulphate solution, as per our prior studies. SCC was evaluated from the decrease in tensile strength, ductility and fractography as revealed by scanning electron microscopy observation. A range of SCC susceptibilities was observed.