Large scale molecular dynamics calculations have been carried out to investigate the properties of nanometric helium bubbles in silicon carbide as a function of helium density and temperature. A dedicated interatomic potential has been developed to describe the interactions between helium and SiC atoms. The simulations revealed that the helium density cannot exceed a certain threshold value, which depends on temperature, because of the plastic deformation of the SiC matrix. Both local amorphization at low temperatures, and nucleation and propagation of dislocations at high temperatures, have been identified as activated plasticity mechanisms. This work also predicts that very high pressure, up to 60 GPa could be reached in helium bubbles in silicon carbide.

已经进行了大规模的分子动力学计算，以研究碳化硅中纳米氦气泡随氦密度和温度变化的特性。已经开发出专用的原子间势来描述氦和SiC原子之间的相互作用。模拟表明，由于SiC基体的塑性变形，氦气密度不能超过取决于温度的特定阈值。低温下的局部非晶化以及高温下位错的形核和扩散都被认为是活化的可塑性机制。这项工作还预测，碳化硅中的氦气气泡可达到高达60 GPa的极高压力。