【摘要】 采用电子能量损失谱(EELS)研究了不同商用钢铁材料的晶界,计算了晶界处和晶粒内铁原子的3d电子占据态密度,并将其和晶界性质以及材料的宏观断裂性能相联系.结果表明:当样品晶界处铁原子的3d电子占据态密度高于晶粒内时,晶界结合强度低于晶内,晶界表现出脆性,材料的冲击断裂方式主要为脆性的沿晶断裂;反之,如果晶界处铁原子的3d电子占有态密度与基体没有明显的差异,则晶界结合强度与晶内相当,晶界表现出韧性,材料的断裂方式主要为韧性的穿晶断裂.更多还原

【Abstract】 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.更多还原