Calculation On Mechanical And Thermal Propertiesand Energy Band Of Intermetallic Compounds In Ti-Al

Ti-Al alloy is one of the most important materials,which has been widely used because of its excellent physical properties.In the design and application of Ti-Al alloy,often need to have a deeper understanding and mastery of the relevant mechanical and thermal properties and electronic structure,Therefore,the paper has important theoretical significance and value in the calculation on mechanical and thermal propertiesand energy band of intermetallic compounds in Ti-Al.The mechanical and thermal properties and energy band of the intermetallic compounds TiAl,TiAl₂,TiAl₃ and Ti₃ Al in the Ti-Al alloys were theoretically calculated based on density functional theory（DFT）and first principles,using the software package of CASTEP of Materials Studio.In the process of calculation,firstly,the crystal structure of GGA is optimized by using the PBE method in the generalized gradient approximation.On this basis,the formation enthalpy and cohesive energy of four kinds of intermetallic compounds were calculated by using the corresponding formulas of heat and energy.The elastic coefficient of each phase of Ti-Al alloy was calculated by the PW91 method in the generalized gradient approximation（GGA）.The electron energy band and electron state density curves are calculated,and the results are theoretically analyzed.The calculation results show that the compounds in the four kinds of metal,the heat of formation,the binding energy calculation results shows that the formation of the strongest in the four phase of Ti-Al alloy Ti₃ Al alloy,and the structure is the most stable,through the calculation of the elastic coefficient of the four phase of the analysis of various elastic coefficient.The Ti₃ Al phase is toughness,and anti deformation ability is the strongest,rigidity is also the strongest,shows good mechanical properties.Through the calculation and analysis of the energy band and the density of States,the above four kinds of alloys belong to metallic materials,but the metallicity of TiAl₃ is weaker than that of the other three materials.These results are consistent with the conclusions given by other criteria.The results of this paper provide a useful reference for the relevant theoretical and applied research.