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采用基于密度泛函理论的第一性原理方法,通过计算研究了Pt-Ir-Y系金属间化合物的生成焓和结合能、电子结构、弹性性质和结构稳定性.计算结合能和生成焓可以得出,在Pt-IrY系合金中,最容易生成Ir_2Y,其合金相也是最稳定的.由态密度图可以得出,合金稳定性顺序为Ir Y>Pt_3Y>Pt_4Y_5>Pt_2Y>Ir_2Y.由态密度图可以看出Ir-Y系中赝能隙较宽,说明Ir、Y较Pt、Y更容易生成化合物.由弹性常数,体模量B、切变模量G、弹性模量E、和泊松比ν得Pt-Ir-Y系五种金属间化合物中强度大小顺序为:Ir_2Y>Pt_2Y>Pt_3Y>IrY>Pt_4Y_5由塑脆转变的依据得,Pt-Ir-Y系五种金属间化合物中都有较好的塑性,其中塑性最好的为Pt_4Y_5.
The enthalpies of formation, the binding energies, the electronic structures, the elastic properties and the structural stability of the Pt-Ir-Y intermetallic compounds were calculated by the first principles method based on the density functional theory. The calculated binding energy and enthalpy of formation can be calculated It is concluded that Ir2Y is most likely to be formed in Pt-IrY alloys and the alloy phase is the most stable. From the density of states diagram, the order of the stability of the alloys is Ir Y> Pt_3Y> Pt_4Y_5> Pt_2Y> Ir_2Y. Density diagram shows that the pseudogap of Ir-Y system is wide, which shows that compounds Ir and Y are easier to generate than Pt and Y. The elastic constants, bulk modulus B, shear modulus G, elastic modulus E, and Po The order of the intensities of the Pt-Ir-Y series of five intermetallic compounds is as follows: Ir_2Y> Pt_2Y> Pt_3Y> IrY> Pt_4Y_5 Based on the transition from plastic to brittle, Pt-Ir- Have better plasticity, plasticity best for Pt_4Y_5.