摘要
运用固体与分子经验电子理论,建立Fe-Cu二元合金固态时效过程中基体及析出相的价电子结构模型,从电子层次揭示Fe-Cu合金强化机理。理论计算结果表明,合金中Cu原子与Fe原子通过化学键结合,其时效峰值处所形成的类B2结构亚稳相的最强和次强键的共价电子对数远高于合金基体α-Fe晶胞的最强和次强键,同时析出相各键的结合能也高于合金基体,这种较强的Fe-Cu键形成规则排列,使得Fe-Cu最强键上的共价电子对数增加,起到提高合金整体键强的作用。同时,高键能的Fe-Cu偏聚形成的析出相会增加位错运动的阻力,使合金的强度得到明显提高。利用EET理论预测Fe-Cu析出强化结果与实测结果吻合良好,验证了该方法的有效性和可靠性。
Valence electron structure model of matrix and precipitates of Fe-Cu binary alloys are established by using empirical electron theory（EET） of solids and molecules,to reveals the Fe-Cu alloy strengthening mechanism from the electronic level.Theoretical results show that the Cu and Fe atoms form by chemical bonds in alloy,the covalent electron pairs of the strongest and the second strong bond of the metastable B2-like structure phase,which formed in the aging peak,is far stronger than that of α-Fe matrix cell,and the bond binding energy of precipitates is higher than the matrix as well.The strong Fe-Cu bonds arranged regularly,increases the covalent electron pairs of Fe-Cu strongest bond,and stabilize total bond of the alloy.At the same time,high bond energy Fe-Cu precipitates increases the resistance of dislocation motion,and strengthen the alloy.There is a good agreement between the EET theory analysis and experimental results for Fe-Cu precipitation hardening,so the reliability of the method is validated.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2011年第18期33-36,共4页
Journal of Mechanical Engineering
基金
国家自然科学基金(50361001)
内蒙古自然科学基金(2009MS0809)资助项目
关键词
Fe-Cu合金
强化
价电子结构
经验电子理论
Fe-Cu alloy Strengthening Valence electron structure Empirical electron theory
