Electronic Structure Characterization of Bonding of Grain Boundaries and Fracture Mode of Steels
钢铁材料晶界性质和冲击断裂特征的电子结构表征

Electron energy loss spectroscopy (EELS) was used to study grain boundaries in steels. The normalized 3d occupancies of states of irons both in bulk and at grain boundary were calculated according to the EELS data which are related to the change in the bonding of grain boundaries and the fracture mode of the steels. It is found that if the grain boundary (GB) has a higher occupancy of 3d states of iron than that of the bulk, the sample has a weak bonding of GB and tends to intergranular fracture. Otherwise if the GB has almost the same occupancy of 3d state of iron as the bulk, the sample has a strong bonding of GB and tends to transgranular fracture.