Insights into solute atom doping effects on mechanical properties and grain boundary behaviors in β-Ti∑5(310)
摘要
First-principles calculations are employed to examine the impact of forty-eight metallic atoms on segregation and strength at β-Ti∑5(310) grain boundary (GB). The study starts by determining the solution energy of metallic atoms within the lattice, and conducting a preliminary analysis of the solubility of these atoms in the matrix. The theoretically calculated results of the solution energies correspond well to the difficulty of alloying in the experimental process. Subsequently, segregation energy is computed, and those atoms segregating near the GB are identified. Based on the Rice-Wang theory, the strengthening energy of segregated atoms near the GB is calculated, and the resulting effects on strengthening, embrittlement, and weakening are analyzed. To validate the findings, a first-principle tensile test is conducted on Be, Ge, Co, Rh, and Ir. The results indicate the following trend of the strengthening effect: GB + Be > GB + Co > GB + Rh > GB + Ir > GB + Ge > GB, which is consistent with the Rice-Wang grain boundary strengthening/embrittlement evaluation system. This comprehensive investigation contributes to a deeper understanding of the mechanical properties of β-Ti∑5(310) systems.
Graphical abstract