中南大学学报（自然科学版）2017，Vol.48Issue(2)：325-330,6.DOI:10.11817/j.issn.1672-7207.2017.02.008
强磁场对铝基复合材料中位错密度的作用机制
Mechanism of high magnetic field on aluminum matrix composites dislocation density
摘要
Abstract
The in-situ Al2O3 and Al3Ti multi-phases reinforced 7055 aluminum matrix composites were fabricated. The particle size of Al2O3 was at nanometer level and that of Al3Ti was at micron level. The particles dispersed evenly in the matrix and the interface exhibited better wettability. Then the composites were processed in high pulsed magnetic field at room temperature. The magnetic induction intensityB was controlled at 1, 2, 3, 4 and 5 T separately. The results show that the dislocation density (ρ) and effective microstraine increase withB enhancement. WhenB=5 T,ρ ande tend to be saturated. It is shown that the increase ofρ is not attributed to magnetic pressure or magnetic force while magnetoplasticity effect is induced by high magnetic field. That is to say, the magnetic field influences the movements of electrons and atoms in quantum scale, which enhances the atomic diffusion rate and interactions between dislocations. It reduces the dislocation nucleation kinetic barrier, which makes the dislocation multiply. However, the resistance force in inner crystal increases with the increase of microstrain, which leads to the saturation of dislocation density.关键词
铝基复合材料/脉冲磁场/位错/磁致塑性Key words
aluminum matrix composites/pulse magnetic field/dislocation/magnetoplasticity分类
矿业与冶金引用本文复制引用
王宏明,彭琮翔,李桂荣,李沛思..强磁场对铝基复合材料中位错密度的作用机制[J].中南大学学报（自然科学版）,2017,48(2):325-330,6.基金项目
国家自然科学基金资助项目(51371091,51174099) （51371091,51174099）
江苏省自然科学基金资助项目(BK2011533)(Projects(51371091, 51174099) supported by the National Natural Science Foundation of China （BK2011533）
Project(BK2011533) supported by the Natural Science Foundation of Jiangsu Province) （BK2011533）
