摘要
Up to now,it remains unclear how normal stress affects the deformation mode transition of metallic glasses(MGs)at high temperatures.Here by constructing the deformation maps under both compression and tension,we show that the tensile normal stress can largely promote the transition from shear localization to homogeneous deformation while the compressive one may slightly suppress it,demonstrating a significant normal stress effect.The present results emphasize the critical role of stress state in high-temperature deformation of MGs,implying that the thermoplastic forming of MGs could be better controlled via adjusting the local stress state.
正应力如何影响金属玻璃高温下的变形方式转变目前仍不清楚.本文通过同时构建金属玻璃在压缩和拉伸下的变形图,发现存在显著的正应力效应,即拉伸正应力能极大地促进剪切局域化到均匀变形的转变,而压缩正应力则可能轻微抑制该转变.本研究结果强调了应力状态在金属玻璃高温变形中的关键作用,并预示着可通过调整局部应力状态来更好地控制金属玻璃的热塑性成形.
基金
supported by the National Natural Science Foundation of China(51771205)
Liaoning Revitalization Talents Program(XLYC1808027)。
