A New Atomistic Mechanism for Heterogeneous Nucleation in the Systems with Negative Lattice Misfit: Creating a 2D Template for Crystal Growth

Heterogeneous nucleation is a widespread phenomenon in both nature and technology. However, our current understanding largely confined to the classical theory (CNT) postulated over century ago, which heterogeneous occurs stochastically form spherical cap facilitated by substrate. In this paper, we show that systems with negative lattice misfit completes deterministically within three atomic layers structural templating two-dimentional template from new phase can grow. Using molecular dynamics (MD) simulations of generic system containing metallic liquid (Al) substrate variable (fcc fixed Al atoms), found proceeds layer-by-layer: first layer accommodates through partial edge dislocation network; second twists an angle screw network reduce distortion; third creates crystal plane solid (the 2D nucleus) templates further growth. The twist relative as signature has been validated high resolution transmission electron microscopic (HRTEM) examination TiB2/Al TiB2/?-Al15(Fe, Mn)3Si2 interfaces two different Al-alloys.