摘要
采用半固态搅拌铸造法制备AlSi7-SiC复合材料,并利用真空压铸工艺实现了其近净成形,结合第一性原理计算方法研究了共晶Si对SiC颗粒和基体界面结合强度的影响.结果显示,在AlSi7-SiC复合材料中,发现较为严重的共晶Si偏析现象,当SiC颗粒同时处于共晶Si和α-Al边界时,形成了少量的共晶Si夹杂、被大量共晶Si包裹、完全被共晶Si包裹三种典型的界面.第一性原理计算结果显示,在C端和Si端的Si/SiC界面中,弛豫后topSi 1配位方式具有最大的粘附功,与Al/SiC界面相比,Si/SiC界面具有更高的结合强度.Si偏析相提高了界面处的电荷密度,因而具有更好的界面结构稳定性.
AlSi7-SiC composite was prepared by semi-solid stirring casting, and its near-net shape forming was achieved by vacuum die casting. The influence of eutectic Si segregation on the interface strength of SiC-Al composite was studied by the first principles calculation method. The results shown that a mass of eutectic Si segregation was found in the matrix of the prepared AlSi7-SiC composites and three typical interfaces were formed: mixed up with a few eutectic Si, a half trapped in eutectic Si and completely trapped in eutectic Si. The calculation results shown that the Si/SiC interface with C-terminated and Si-terminated, the topSi 1 coordination mode has the largest adhesion work after relaxation. The interface bonding strength of the Si/SiC interface is greater than that of the Al/SiC interface. Compared with the Al/SiC interface, the Si/SiC interface had a better stability of interface structure attributed to the strong covalent bond formed at the Si/SiC interface and the segregated Si phase improved the interfacial charge density.
作者
肖鹏
胡启耀
邓昀麒
XIAO Peng;HU Qi-Yao;DENG Yun-Qi(School of Aeronautical Manufacturing Engineering,Nanchang Hangkong University,Nanchang 330063,China)
出处
《原子与分子物理学报》
北大核心
2024年第5期159-168,共10页
Journal of Atomic and Molecular Physics
基金
江西省自然科学基金(20192BAB20003)
江西省金属材料微观结构控制重点实验室开放基金(EJ201903061)
校级“课程思政”示范课程建设经费(SZ22118)
校级教改课题(JY21026)。
