The effect of rotating magnetic field on the microstructure of in situ TiB2/Cu composites

4th International Conference on Advances in Solidification Processes

材料科学;物理学

Zou, C.^1 ; Kang, H.^1 ; Li, R.^1 ; Li, M.^1 ; Wang, W.^1 ; Chen, Z.^1 ; Wang, T.^1

Key Laboratory of Materials Modification, Ministry of Education, School of Materials Science and Engineering, Dalian University of Technology, Dalian

116024, China^1

关键词: Homogenous dispersions;    Induction furnace;    Magnetic-field intensity;    Medium frequencies;    Particle aggregation;    Particle distributions;    Particles distribution;    Rotating magnetic fields;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/117/1/012043/pdf
DOI  :  10.1088/1757-899X/117/1/012043

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Nano ceramic particulate reinforced metal matrix composites are confronted with the problem of particle aggregation emerging in the process of solidification. It sharply deteriorates the mechanical properties of the composites. In order to improve the microstructure and particle distribution, in situ TiB2/Cu composites were prepared using Ti and Cu-B master alloys in a vacuum medium frequency induction furnace equipped with a rotating magnetic field (RMF). The effect of RMF magnetic field intensity employed on the microstructure and particles distribution of the TiB2/Cu composites were investigated. The results show that with the applied RMF, TiB2particles are homogeneously distributed in the copper matrix, which significantly improves the mechanical properties of TiB2/Cu composites. The mechanism of RMF may be ascribed to the following two aspects. On the one hand, the electromagnetic body force generated by appropriate RMF drives forced convection in the equatorial plane of composite melt during solidification. On the other hand, a secondary flow in the meridional plane is engendered by a radial pressure gradient, thus making a strong agitation in the melt. These two effects result in a homogenous dispersion of TiB2particles in the copper matrix, and hence excellent properties of TiB2/Cu composites were obtained.