Ta和Re对Ni/Ni_(3)Al相界面断裂强度和蠕变强度的影响  

Effect of Ta and Re on the fracture strength and creep strength of Ni/Ni_(3)Al interface

作　　者：胡雪兰[1] 孙小清 王梦媛 王亚如 Hu Xue-Lan;Sun Xiao-Qing;Wang Meng-Yuan;Wang Ya-Ru(Sino-European Institute of Aviation Engineering,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学中欧航空工程师学院,天津300300

出　　处：《物理学报》2023年第6期72-80,共9页Acta Physica Sinica

基　　金：中央高校基本科研业务费(批准号:3122018Z004)资助的课题.

摘　　要：采用基于密度泛函理论和广义梯度近似的第一原理方法,探究Ta元素和Re元素在Ni/Ni_(3)Al相界面中的相互作用及其对界面强度的影响.计算表明:在绝大多数化学计量比范围内, Ta原子优先占据γ相中的顶点Ni位, Re原子优先占据γ'相中的Al位, Re原子和Ta原子共合金化时掺杂位置不发生改变.通过格里菲斯断裂功、不稳定堆垛层错能及空位迁移能的计算,得出Ta和Re合金化都可以增强界面的格里菲斯断裂能,提高界面的结合强度,两种合金化元素均提高了体系的不稳定堆垛层错能,即提高了界面阻碍位错运动的能力和抵抗变形的能力,其中Re的单独合金化效果更好.两种元素的掺杂提高了界面上空位迁移的势垒,阻碍了空位的发射和吸收,进而提高了合金的蠕变能力.The first principle method based on density functional theory and generalized gradient approximation is used to investigate the interaction of Ta and Re elements at Ni/Ni_(3)Al interface and their influence on the interface strength.According to the calculations of the dissolution energy of these two alloying elements at 7 different positions,it can be concluded that in most of the stoichiometric ranges,Ta atoms preferentially occupy Ni sites in the g phase,while Re atoms occupy preferentially Al sites in γ' phase.The doping positions do not change when these two atoms are co-alloyed.The calculation of Griffith fracture work of Ni/Ni_(3)Al interface system shows that the doping of Ta atoms can improve the interface fracture strength of the phase boundary region between the γ/γ' coherent atomic layer and g atomic layer.The interface is easier to fracture in the phase boundary area between γ/γ' coherent atomic layer and γ' atomic layer after Ta atoms have been doped.The doping of Re atoms can improve the interface fracture strength of the phase boundary region between γ/γ'coherent atomic layer and γ' atomic layer.The interface is easier to break in the phase boundary area between γ/γ' coherent atomic layer and γ atomic layer.The calculation results of the unstable stacking fault energy under the interface slip system [110](001) before and after Ta and Re alloying show that the doping of these two types of atoms increases the value of the unstable stacking fault energy of the interface,and the slip system [110](001)becomes difficult to start,which enhances the ability of the interface to block the movement of dislocations,thus enhancing the creep strength of the nickel base superalloy.When doping Re atoms,the effect is greater,and the unstable stacking fault energy of the interface increases by 11.1%,which is better for improving the creep strength of the system.By studying the influence of alloying atoms on the path of vacancy migration and the energy barrier,it is concluded that the doping of Ta and Re

关 键 词：第一性原理计算 Ni/Ni_(3)Al相界面 合金化元素Ta和Re 界面强度 

分 类 号：O346.1[理学—固体力学] TG132[理学—力学]