中文摘要：

采用Tersoff势对具有不同截面尺寸的β-SiC纳米丝的[001]向拉伸力学性能进行了分子动力学模拟，得到了纳米尺度下β-SiC纳米丝的应力-应变演化关系，研究了β-SiC纳米丝的力学性能与特征尺寸的关系．模拟结果表明，β-SiC纳米丝在常温下具有不同于宏观陶瓷材料的室温脆性，在断裂前发生了明显的塑性变形，塑性应变达到11％．截面尺寸对纳米丝的力学性能有显著的影响，截面尺寸越大，初始杨氏模量越大，抗拉强度越高．

英文摘要：

The tension mechanical properties of the [001] β-SIC nanowires with different crosssections were investigated using molecular dynamics simulation with Tersoff bond-order interatomic potential. The stress-strain curves were obtained and analyzed in order to elucidate the scale effect on the mechanical properties of the nanowires. The simulation results show that the β-SiC nanowires exhibit large plastic deformation for at least 11% under axial strain at room temperature, which is rarely observed for their macro counterparts especially at low temperature. It is also found that the influence of the cross section size of the nanowires on the mechanical properties is remarkable; with increasing of the size the tensile strength and Young＇s modulus of the nanowires increase.