Ab initio calculations of elastic properties of Ni3Al and TiAl under pressure

The structural parameters and the elastic stiffness coeffcients of Ni3Al and TiAl under a pressure P were computed by the ab initio pseudopotential method with the plane-wave basis set and the generalized gradient approximtion (GGA). The pressure dependence of the elastic constants is an important character-istics for both Ni3Al and TiAl as these materials are frequently subject to varying pressures during proc-essing. The bulk modulus was also calculated. Stress–strain relationships were used to obtain the elastic constants. The results are in good agreement with the available experimental data. Key words: ab initio calculations; density functional calculations 1