A first-principles study on influences of metal species Al, Zr, Mo and Tc on mechanical properties of U3Si2
The first-principles approach is employed to study the influences of metal species Al, Zr, Mo and Tc on the mechanical properties of U3Si2. When the Al, Zr, Mo and Tc atoms diffuse into the vacancy sites, they will dissolve into the lattice confirmed from the solution energies. It is found that the compounds of U3Si2 with low amount of Al, Zr, Mo, and Tc in Si vacancies or Al, Zr, and Mo in U vacancies can behave in the manner of ductility. But for the cases with Al, Zr, Mo and Tc in the interstitial sites, all the compounds are demonstrated to be brittle. Furthermore, the stress-strain relationship for the U3Si1.9375Mo0.0625 system is calculated which illustrates the enhanced ductility. The current results may indicate the substitution of Si by carefully selected metal atoms can enhance the performance of U3Si2.