Numerical investigation on thermal properties at Cu–Al interface in micro/nano manufacturing

A hybrid model by integrating TTM (two-temperature model) and MD (molecular dynamics) is proposed to investigate the properties on interface of dissimilar materials under thermal flux conditions. This model can describe the electron phonon coupling and phonon scattering at the interface of different metals easily. By comparing the Cu–Cu interface and Cu–Al interface, the atoms of the Cu–Cu interface at different sides tend to move together; while, the atoms displacements of Cu and Al are opposite along the interface, which may cause stress and voids at the interface. Moreover, the propagation mechanisms of nanocracks and the corresponding change of temperature distribution and thermal flux are investigated. The results show that the interfaces of dissimilar materials are prone to crack initiations, leading to delaminations because of the high temperature. All these are useful for understanding the deformation and failure of the interfaces structures. It implies a potential method for design and analysis of interface structure in micro/nano manufacturing.