Plasticity and melting characteristics of metal Al with Ti-cluster under shock loading

Impurity agglomeration has a significant influence on shock response of metal materials. In this paper, the mechanism of Ti-clusters in metal Al under shock loading is investigated by non-equilibrium molecular dynamics simulations. Our results show that the Ti-cluster has obvious effects on the dislocation initiation and melting of bulk Al. First, the Ti clusters induces the strain concentrate and leads the dislocations to be initiated from the interface of Ti cluster. Second, dislocation distribution from the Ti-cluster model results in a formation of a grid-like structure, while the dislocation density is reduced compared with that from the perfect Al model. Third, the critical shock velocity of dislocation from the Ti-cluster model is lower than from perfect Al model. Furthermore, it is also found that the temperature near the interface of Ti-cluster is 100 K-150 K higher than in the other areas, which means that Ti-cluster interface melts earlier than the bulk area.