Nitrogen-doping effect on glass formation and primary phase selection in Cu-Zr-Al alloys

Effects of nitrogen doping on the glass formation and primary precipitate phase in a ternary Cu-Zr-Al alloy were investigated. An optimized doping level of nitrogen (∼1000 appm) can improve the glass-forming ability of Cu ₄₉Zr₄₄Al₇ alloy. The type of primary phases from ZrCu (B2) to an unknown Zr- and Al-rich crystalline phase with chemical atomic composition of around Cu₃₈Zr₄₉Al₁₃ in the bulk glassy matrix is controllable by the micro-adjustment of N concentration, which can be utilized as an effective way to design BMG-based composites with selective second phase particles.