摘要
根据固体与分子经验电子理论(EET),采用键距差法(BLD),分析并计算了C11b型金属间化合物MoSi2的价电子结构与理论键能;采用合金元素Al部分取代MoSi2晶格中的Si原子,依据固体与分子经验电子理论在代位式固溶体中的平均原子模型,分析并计算了C11b型Mo(Si0.95,Al0.05)2的价电子结构与理论键能。结果表明:Al微合金化改变了Mo原子和Si原子的杂化状态,从而使相应的价电子结构参数发生变化。与MoSi2相比,Mo(Si0.95,Al0.05)2固溶体中共价电子数在总价电子数中所占的比例(η)由65.87%降至64.28%,因而Al微合金化不利于MoSi2强度的提高;但是晶格电子数由4.7141增至4.9202,所以Al微合金化有利于MoSi2塑性的改善。
According to the empirical electron theory （EET） of solid and molecule, the valence electron structure and theoretical bond energy of C11b-MoSi2 were calculated by the bond length difference （BLD） method. The effects of partial substitution of Al for Si of MoSi2 lattices were considered. According to the average atom model in substitutional solid solutions of EET, the valence electron structure and theoretical bond energy of C11b Mo（Si0.95,Al0.05）2 were analyzed and calculated. The results show that the hybridization state of Mo and Si atoms is altered with Al addition in MoSi2, and then the parameters of valence electron structure change. Compared with MoSi2, the proportion of covalent electrons in total valence electrons decreases from 65.87% to 64.28% and therefore it is concluded that the strength of MoSi2 can be reduced by microalloying with aluminum. However, the lattice electrons increase from 4.7141 to 4.9202, so the plasticity of MoSi2 can be improved by microalloying with aluminum.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2011年第4期595-599,共5页
Rare Metal Materials and Engineering
基金
高等学校博士点基金(20070290523)
江苏省自然科学基金(BK2009096)
中国博士后科学基金(20090461154)
关键词
二硅化钼
铝合金化
价电子结构
molybdenum disilicide
microalloying with aluminum
valence electron structure
