부산대학교 도서관

Fabricating porous active metals through chemical dealloying poses challenges due to their reactivity and vulnerability tooxidation in aqueous solutions. The objective of this study was to create micron-sized porous Ti alloy by utilizing the Ti–Mo system as a precursor alloy for chemical dealloying. The impact of phase composition and initial microstructure of theprecursor alloys (Tix at% Mo100 − x at%, x = 60 ~ 70) on the morphology of the resulting porous Ti alloy was systematicallyinvestigated. To improve the mechanical strength and minimize oxidized phases during the dealloying process, a molten saltelectrolysis (MSE) method was employed. The strengthening mechanism of MSE on porous Ti alloys encompassed three keyaspects. Firstly, it effectively reduced the presence of oxidized phases, thereby eliminating surface defects. Secondly, MSEfacilitated grain growth and eliminated voids and cracks at the grain boundaries, leading to enhanced mechanical properties. Thirdly, the involvement of a secondary phase contributed to the overall strengthening mechanism. Following MSE treatment,the oxygen content in the porous Ti alloy decreased from over 13 to 5 at%, and needle-like nanocrystalline β-Ti precipitatesformed within the ligament structure. The accumulation and aggregation of compression-induced dislocations at the grainboundaries of the precipitated phase further improved the mechanical properties. In summary, this work presents an innovativeapproach to fabricating porous Ti alloy with low oxygen content, high strength, and adjustable microstructure. It elucidatesthe strength enhancement mechanism by MSE, providing insights for future materials development and applications.