Cu-Ni-Sn合金中微合金元素析出相的第一性原理计算与分析  

First-principle Calculation and Analysis of Microalloying Element Precipitates in Cu-Ni-Sn Alloy

作　　者：彭广威 魏祥[1] 何延钢 匡朝平 Peng Guangwei;Wei Xiang;He Yan'gang;Kuang Chaoping(Hunan University of Humanities,Science and Technology;Hunan Automotive Engineering ocational College;Agricultural Comprehensive Service Center of Qingshuping Town of Shuangfeng County)

机构地区：[1]湖南人文科技学院 [2]湖南汽车工程职业学院 [3]双峰县青树坪镇农业综合服务中心

出　　处：《特种铸造及有色合金》2023年第1期77-82,共6页Special Casting & Nonferrous Alloys

基　　金：湖南省自然科学基金资助项目(2019JJ70058)。

摘　　要：利用第一性原理计算了Cu-Ni-Sn合金中微合金化元素析出相的稳定性和力学性能。结果表明,Si、Nb、V、Zr、Al、Ta、Ti等合金元素形成的Ni_(3)M相比对应结构Ni_(3)Sn相的形成能更低、更稳定,可先于Ni_(3)Sn相析出,阻碍Ni_(3)Sn的析出与长大。Sn、Zr、Ti元素只能和Cu形成部分结构相,且形成能远高于相应的Ni_(3)M相。因此,合金元素在Cu-Ni-Sn合金时效析出的主要强化相为D0_(22)和L1_(2)结构Ni_(3)M有序相。Si、Zr、Al、Ti与Ni形成的L1_(2)和D0_(22)有序相不仅形成能低于相应结构的Ni_(3)Sn,而且弹性模量大于相应结构的Ni_(3)Sn,而L1_(2)结构的Ni_(3)Nb比同结构的Ni_(3)Sn的弹性模量更高。因此,Si、Nb、Zr、Al、Ti等合金元素在Cu-Ni-Sn合金中可通过形成热力学和弹性力学性能更稳定的Ni_(3)M相而实现第二相析出强化。The stability and mechanical properties of precipitates of microalloying elements in Cu-Ni-Sn alloy were calculated by first-principles. The results indicate that the formation energies of Ni_(3)M phase formed by Si, Nb, V, Zr, Al, Ta and Ti are lower and more stable than those of Ni_(3)Sn phase, which can precipitate before Ni_(3)Sn and hinder the precipitation and growth of Ni_(3)Sn phase. Sn, Zr and Ti can only form part of the structural phase with Cu, and the formation energies are much higher than that of the corresponding Ni_(3)M phase. Therefore, the strengthening phases precipitated in Cu-Ni-Sn alloy are mainly D0_(22)and L1_(2)Ni_(3)M ordered phases. The L1_(2)and D0_(22)formed by Si, Zr, Al, Ti and Ni not only form Ni_(3)Sn phase with lower energy than the corresponding structure, but also have higher elastic modulus than the Ni_(3)Sn phase with the corresponding structure, while the Ni_(3)Nb phase with L1_(2)structure has a higher elastic modulus than the Ni_(3)Sn phase with the same structure. Therefore, Si, Nb, Zr, Al, Ti elements can realize the precipitation strengthening of the second phase by forming Ni_(3)M phase with more stable thermodynamics and elasticity in Cu-Ni-Sn alloy.

关 键 词：CU-NI-SN合金 第一性原理 微合金化元素 析出相 

分 类 号：TG146.11[一般工业技术—材料科学与工程]