Correlation of bonding of grain boundary and fracture mode with local electronic structure in steels by electron energy loss spectroscopy

Electron energy loss spectroscopy (EELS) was used to study bonding of grain boundaries (GBs) in various types of commercial steels. It is found that if the GB has a higher occupancy of 3d states of iron than that of the grain, the sample tends to fracture intergranularly. Otherwise if the GB has a lower occupancy of 3d state of iron than the grain, the sample would have a strong GB bonding and tends to fracture transgranularly. It is proposed that EELS can estimate the GB cohesion and its impact on the fracture mode of commercial steels. (c) 2007 American Institute of Physics.