Agcl-Induced Hot Salt Stress Corrosion Cracking In A Titanium Alloy

The mechanism of AgCl-induced stress corrosion cracking of Ti-6246 was examined at 500 MPa and 380 degrees C for 24 h exposures. SEM and STEM-EDX examination of a FIB-sectioned blister and crack showed that metallic Ag was formed and migrated along the crack. TEM analysis also revealed the presence of SnO2 and Al2O3 corrosion products mixed into TiO2. The fracture surface has a transgranular nature with a brittle appearance in the primary alpha phase. Long, straight and non-interacting dislocations were observed in a brittle appearance fractured primary alpha grain, with basal and pyramidal traces. This is consistent with a dislocation emission view of the cracking mechanism.