Induced Plasticity of a Brittle （La, Ce）-Based Bulk Metallic Glass by Surface Corrosion

• Published in: 金属学报：英文版 2016 (2), p.129-133
• Main Author: Ji-Juan Liu Ran Li Lian-Xiang Fang Ju Wang Tao Zhang
• Format: Article
• Language: English
• Subjects: H2SO4溶液; 块体金属玻璃; 块体非晶合金; 大块金属玻璃; 室温塑性; 浸泡时间; 腐蚀缺陷; 表面腐蚀
• ISSN: 1006-7191; 2194-1289

Unexpected facture without any room-temperature plasticity severely limits potential structural applications of bulk metallic glasses （BMGs）, especially La-, Mg- and Fe-based ones. In this study, a simple free corrosion method was provided to improve the plasticity of a brittle （La, Ce）-based BMG by the introduction of high-density corrosion defects on the surface. The influences of immersing time in 0.1 mol/L H2SO4 aqueous solution on the surface morphology and mechanical properties of the BMG were evaluated. With increasing immersing time from 5 to 30 min, the degree of surface corrosion increased obviously, and the distribution of corrosion defects became more homogenous. In the samples, the yielding phenomenon and certain plasticity appeared up to 0.3% after the surface treatment. The yielding and plasticity can be attributed to easier nucleation of shear bands on the defect surface rather than on the glabrous surface. The results provided a novel method to improve the plasticity of BMGs.