Al-Zr系金属间化合物的第一性原理研究

The First-Principle Study of Al-Zr Intermetallic Compounds

利用基于密度泛函理论的第一性原理赝势平面波法,计算了Al-Zr系3种金属间化合物在0 K时的生产焓、结合能及相关弹性性能,表征了Al_3Zr、Al_2Zr和AlZr 3种化合物的结构稳定性、硬度和韧/脆性等,并结合总态密度和分波态密度等电子结构分析,揭示了化合物韧/脆性机制。研究表明:Al_3Zr、Al_2Zr和AlZr 3种化合物的结构均具有稳定性,Al_2Zr在所计算的化合物中具有最高硬度,Al_3Zr次之,AlZr最低,且所有化合物均表现为脆性。结合电子结构发现,3种化合物的Al的3s、3p轨道和Zr的4d轨道的价电子具有强烈的杂化作用,从而形成共价键,并导致材料具有低温脆性。

Enthalpy, cohesive energy and elastic performance of three kinds of intermetallic compounds in binary A1-Zr compounds at 0 k were calculated with first-principles pseudopotential plane-wave methods based on the functional theory in order to predict the structure stability, hardness and ductile/brittle, etc. Furthermore, the mechanism of the ductile/brittle of compounds was studied with the electronic structure, such as the total density of states and partial wave state density. The results show that the three compounds of A13Zr, A12Zr and A1Zr have stability structure, and A12Zrcompound has the electronic structure Zr in 4d orbital in highest hardness and all compounds are indicated that valence electrons of A1 in 3 s three compounds have strong hybrid effect, A1-Zr and making materials have low temperature brittleness. characterized by brittle. Analysis of and 3p orbital and valence electrons of thus forming a covalent bond between