摘要
基于"团簇+连接原子"局域结构模型,从团簇内部和团簇间原子的关联作用出发,分析非晶合金的局域结构与非晶合金玻璃化转变、形成能力、热稳定性和力学性能之间的关系。并通过分析模型结构中微合金化元素的占位及其对周围原子关联作用的影响,理解非晶合金的微合金化机理。结果表明,团簇内部原子的关联作用对非晶合金的热稳定性有较大影响,而非晶合金的玻璃化转变、形成能力和力学性能主要受到团簇间原子关联作用影响。并以Si合金化Fe-B二元非晶合金及前过渡元素(Zr、Hf、Nb或Ta)和稀土元素(Y、Ce、Pr、Nd、Sm、Gd或Dy)微合金化Fe-B-Si三元非晶合金对所提理论进行实验验证,两者吻合较好。该研究为理解非晶合金的局部结构-性能关联和微合金化元素作用机理提供了新思路。
Fe-based amorphous alloys are well known for their excellent soft magnetic and mechanical properties such as high saturation magnetization(Bs),very low coercive force(Hc),high magnetic permeability(μ),low core loss,and high strength,and they are suitable for application as transformer-core materials and have potential applications as structural materials.The minor addition of early transition metal(ETM)such as Zr,Nb,Mo,Hf,Ta,or W can effectively improve the glass-forming abilities,thermal stability,soft magnetic and mechanical properties of Fe-based metallic glasses.The beneficial effects of the minor addition on the glass-forming ability can generally be classified into three aspects:(1)it favors the formation of the unique atomic dense configurations with small free volumes,strong liquid behavior,and high viscosity,which are significantly different from those for conventional metallic glasses;(2)it makes the melts energetically closer to the crystalline state than other metallic melts due to their high packing density in conjunction with a tendency to develop short-range order;(3)it makes the melts more viscous,which leads to slow crystallization kinetics.Despite these advantages,the fundamental theory about the mechanism of the minor addition of ETM in glass formation and properties tailoring is yet to be fully established.In this study,a"cluster plus glue atom"local structure model has been proposed to explore the local structure-property correlation of metallic glasses.The accessibility of calorimetric glass transition(T_g),glass-forming ability,thermal glass stability,and the mechanical properties of metallic glasses are explained in terms of the intra-and inter-atomic cluster correlations in the amorphous structures.Based on the local structure model,the Tgand its composition dependence micro-hardness and strength have been attributed to the inter-cluster correlation,and the enhancement of intra-cluster correlation due to minor alloying would contribute to the enhanced thermal glass stability.The experimental results were verified by alloying the Fe-B-based glassy alloy with Si and alloying the Fe-B-Si-based glassy alloy with ETMs(Zr,Hf,Nb,or Ta)and rare-earth metals(Y,Ce,Pr,Nd,Sm,Gd,or Dy).The experimental results correspond well with theoretical analysis.This study provides a novel understanding of the local structure-property correlation and minor alloying beneficial effects on amorphous alloys.
作者
耿遥祥
王英敏
GENG Yaoxiang;WANG Yingmin(School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China;Key Lab of Materials Modification by Laser,Ion and Electron Beams,Ministry of Education,Dalian University of Technology,Dalian 116024,China)
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第11期1558-1568,共11页
Acta Metallurgica Sinica
基金
国家重点研发计划项目No.2016YFB1100103
江苏省自然科学基金青年基金项目No.BK20180985
江苏省高等学校自然科学研究面上项目No.18KJB430011。
关键词
铁基非晶合金
“团簇+连接原子”模型
结构-性能关联
微合金化机理
实验验证
Fe-based amorphous alloy
"cluster-plus-glue-atom"model
structure-property correlation
minor alloying mechanism
experimental verification
作者简介
耿遥祥,男,1986年生,副教授,博士;通讯作者:耿遥祥,yaoxianggeng@163.com,主要从事激光增材制造专用铝合金、非晶和纳米晶合金的成分设计和性能研究。
