Critical structural invariant during high-pressure solidification of copper

Authors :: Jin, Xiao-Xu
Tian, Ze-An
Hu, Wang-Yu
Source :: MRS Communications; February 2022, Vol. 12 Issue: 1 p45-50, 6p
Publication Year :: 2022
Abstract: Abstract: Molecular dynamics simulation (MD) has been conducted to investigate the pressure effect on microstructure of copper during rapid solidification. The pressure increases the onset temperature (T<subscript>c</subscript>) of nucleation but decreases the energy of atoms and the lattice constant of the final face-centered cubic crystal. Before temperature decreases to T<subscript>c</subscript>the average coordination number (ACN) of atoms and the percentage of topologically close-packed atoms (P<subscript>TCP</subscript>) increase, while the number of types of the largest standard clusters (K<subscript>LaSC</subscript>) decreases and that of the topologically close-packed (K<subscript>TCP</subscript>) atoms is about the same. Interestingly they are pressure-independent constants at T<subscript>c</subscript>, with K<subscript>LaSC</subscript>= 3300, ACN = 13.08, P<subscript>TCP</subscript>= 18.3%, and K<subscript>TCP</subscript>= 33 in the super-cooled copper. Graphical abstract: <fig id="Figa" position="anchor"> <graphic position="anchor" specific-use="HTML" mime-subtype="PNG" href="MediaObjects/43579_2021_138_Figa_HTML.png" id="MO1"></graphic> </fig>