本团队张茂副教授、硕士生杨智芯等在Applied Surface Science发表研究论文。

摘要：This study investigates the high-temperature oxidation behavior of Zr55Cu30Al10Ni5 metallic glass (MG) powders using thermogravimetric analysis combined with multiscale characterization. The powders follow diffusion-controlled parabolic kinetics but oxidize up to four orders of magnitude faster than bulk alloys, owing to curvature-enhanced transport and nanogranular oxide structures that promote short-circuit diffusion. Oxidation produces a stratified scale with an outer Cu-rich layer and inner ZrO2-dominated sublayers. Interfacial porosity indicates diffusion-flux imbalance associated with selective Cu outward migration. Unlike bulk metallic glasses, prolonged oxidation causes spontaneous particle fragmentation driven by growth-induced tangential stress. A fracture criterion shows that the critical oxide thickness scales with the square of the particle radius, leading to a size-dependent instability condition. Based on this scaling, a practical model for critical oxidation time is derived to guide safe thermal exposure in laser powder bed fusion. Particle size thus governs oxidation kinetics, scale integrity, and powder reusability.