中文摘要：

基于固体与分子经验电子理论（EET）,采用平均原子模型计算了质量分数为4%,10%,15%,20%,25%,30%,32%Cu-Zn合金相结构单元的价电子结构参数统计值nA′,Δρ′,利用n′A,Δρ′计算了表征合金强化效果的固溶强化系数SCu-Zn和界面强化系数SCu-Zn/Cu-Zn,它们的数值分别为0.9925,1.0054,1.0437,1.0868,1.1055,1.1205,1.1208和7.6579,8.5444,10.6675,11.8616,12.4737,10.3345,9.5809,并通过两个强化系数讨论了合金元素Zn对Cu-Zn合金固溶强化、界面强化及合金强度出现拐点现象的影响。结果表明,SCu-Zn值越大,合金固溶强化效果越强;SCu-Zn/Cu-Zn值越大,合金的相界面应力越高,抵抗变形能力越强,界面强化效果越好。当Zn含量小于25%时,SCu-Zn,SCu-Zn/Cu-Zn值均随溶质的增加而单调递增,合金强度的变化趋势与SCu-Zn,SCu-Zn/Cu-Zn值变化相同;当Zn含量大于25%时,随着Zn含量增加,SCu-Zn值增势变缓,SCu-Zn/Cu-Zn值急剧下降,但SCu-Zn/Cu-Zn值降低较SCu-Zn值增加趋势大,它们综合作用表现为合金强度降低。SCu-Zn和SCu-Zn/Cu-Zn共同决定着合金的强化效果,它们的数值愈大,合金强化作用愈强。

英文摘要：

Based on the empirical electron theory of solids and molecules（EET）,the statistical values of valence electron structure parameters nA′ and Δρ′ of Cu-Zn alloy phase structure unit,whose mass fractions were 4%,10%,15%,20%,25%,30%,32%,were calculated by using the average atoms model.The solid solution strengthening coefficient SCu-Zn and interface strengthening coefficient SCu-Zn/Cu-Zn characterizing the properties of alloy phase,whose values were 0.9925,1.0054,1.0437,1.0868,1.1055,1.1205,1.1208 and 7.6579,8.5444,10.6675,11.8616,12.4737,10.3345,9.5809 separately,were calculated by using the nA′ and Δρ′.The effects of alloy element Zn on solid solution strengthening,interface strengthening and the inflexion point of alloy strength of Cu-Zn alloy were discussed with the two strengthening coefficient.The results showed that,the larger the SCu-Zn value was,the stronger the effect of solid solution strengthening was;the larger the SCu-Zn/Cu-Zn value was,the higher the interface stress of alloy phase,the stronger the resisting formability was and the better the effect of interface strengthening was.When the mass fraction of Zn was less than 25%,the values of both the SCu-Zn and the SCu-Zn/Cu-Zn increased monotonically with the increment of Zn content,these variation trends of Cu-Zn alloy strength were the same as that of both SCu-Zn and SCu-Zn/Cu-Zn;when the mass fraction of Zn was more than 25%,with the increment of Zn content,the SCu-Zn values increased slowly,and the SCu-Zn/Cu-Zn values fell rapidly,but the reducing trend of SCu-Zn/Cu-Zn values was more serious than the increasing trend of SCu-Zn values,which made the Cu-Zn alloy strength reduce with the synthetic action of the SCu-Zn and the SCu-Zn/Cu-Zn.The strengthening of effects of Cu-Zn alloy was decided by both the SCu-Zn and the SCu-Zn/Cu-Zn;whose values were larger,the strengthening effect of alloy was stronger.