Abstract:In order to explore and characterize the deformation behavior of bcc-Fe grain boundaries from the nanoscale,the tensile and shear deformation processes of four different bcc-Fe Σ3 grain boundaries,i.e. Σ3(111),Σ3(112),Σ3(111)/(115) and Σ3(112)/(552),are investigated by molecular dynamics simulation. The effect of the vacancies and C atoms with different atomic percents on the machanical properties of the four different grain boundaries are discussed. The results indicate that the tensile stress-strain curve yield stage of Σ3(112) grain boundary gradually disappears due to the increase of the atomic percent of the grain boundary occupied by vacancies and C atoms.The tensile strength of Σ3(111)grain boundary gradually decreases with the increases of the atomic percent of vacancies,and the tensile strength of the other three grain boundaries are reduced in different degree. The tensile strength of Σ3(111) grain boundary containing C atoms increases,however,the other three grain boundary tensile strengths are lower than the original defect-free grain boundaries. The shear strength of the four grain boundaries is significantly reduced by the presence of vacancies or the replacement of C atoms.
肖少彬, 王薇, 刘天宇, 张琴, 吕知清. 晶界空位与碳原子对铁晶界力学性能的影响[J]. 钢铁, 2020, 55(4): 75-81.
XIAO Shao-bin, WANG Wei, LIU Tian-yu, ZHANG Qin, LÜ Zhi-qing. Effects of vacancies and C atoms on mechanical properties of Fe grain boundary. Iron and Steel, 2020, 55(4): 75-81.
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