摘要
剪切带是一种材料塑性变形高度局域化的变形模式,广泛存在于非晶体系的形变中,控制着这些无序体系失稳、灾难性断裂行为.传统的非晶体系如岩石,胶体,玻璃和聚合物等因较差的力学性能以及过于复杂的结构而不利于剪切带的实验研究.近几十年来,非晶合金的出现极大丰富了剪切带的研究,推进了对剪切带的认识.通过大量非晶合金中剪切带的实验和理论研究,人们发现剪切带行为具有空间不均匀性和时间不连续性的特征,表现出复杂的动力学特征,和自然界以及物理系统中许多复杂体系的动力学行为相似.同时,剪切带的性质尤其是其动力学行为对非晶合金的宏观力学行为和性能有重要的影响,对理解这类材料的微观变形机理也起着重要的作用.本文结合团队近年来在非晶合金剪切带行为方面的研究结果,对剪切带的运动行为和物理机制进行介绍,包剪切带间歇性运动行为、以及间歇性运动在表征其动力学性质中的作用以及物理机制,以及剪切带的自组织临界行为、物理机制等.最后对非晶合金剪切带行为研究中亟需解决的问题进行了总结和展望.
Shear banding is a localized plastic deformation form that wildly exist in amorphous systems, and plays the decisive role in controlling the failure and plasticity. Due to the localization in space and instantaneous in motions,clarifying the map of shear bands is still a challenge mission. For traditional amorphous systems as rocks, colloid, oxide glasses and polymers, the studies on shear bands are impeded due to the poor mechanical properties or complex structures of these systems. In recent years, the developments of metallic glasses(MGs) overcome this barrier with the abundant mechanical experiments on shear bands in laboratories, which greatly promotes the insights to shear bands. In addition,the dynamics of shear bands have a significant influence to the mechanical properties and behaviors of MGs, which is also of significant importance for understanding the deformation mechanisms of MGs. The insights for the structural origin,morphology, affect area, properties and motions of shear bands has made great progress. With the investigations on MGs,shear mands are found inhomogenous in space distribution and non-steady in time. The behaviors of shear bands show a similarity with that of the complex systems in nature as well as physic areas. This article mainly reviews our recent studies on the complex behaviors of shear bands in MGs, including the serration follow behaviors and the self-organizing criticality(SOC) behaviors of shear bands. The models that quantify these behaviors of shear bands, such as stick-slip model, machine-sample coupling model, are also introduced. The review also identified the key questions remaining to be answered, and presents an outlook for the field.
作者
董杰
王雨田
胡晶
孙保安
汪卫华
白海洋
Dong Jie;Wang Yutian;Hu Jing;Sun Baoan;Wang Weihua;Bai Haiyang(Instiute of Physics,Chinese Academy of Science,Beijing 100190,China;College of Materials Science and Opro Electronic Technology,Universiry of Chinese Academy of Sciences,Beijing 100049,China;School of Materials and Mechanical Engineering,Bejing Technology and Business University,Bejing 100048,China;Songshan Lake Materials Laboratory,Dongguan 523808.Guangdong,China)
出处
《力学学报》
EI
CSCD
北大核心
2020年第2期379-391,共13页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家自然科学基金项目(51822107,51671121,51761135125)
国家重点研发计划项目(2018YFA0703603)
中国科学院战略性先导科技专项(B类)(XDB30000000)
广东省基础与应用基础研究重大项目基金(2019B030302010)资助。
关键词
非晶合金
剪切带
塑性
锯齿流变
滞滑运动
metallic glasses
shear bands
plasticity
serrated flow
stick-slip