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采用基于密度泛函理论的CASTEP程序包,计算了不同压力下Al2Ca相的结构、弹性与电子性能。计算所得0 GPa下Al2Ca的晶格参数与实验和其他理论值相吻合。结果表明:随压力增大,Al2Ca相的体模量B、剪切模量G、杨氏模量E增大,材料的硬度增大;且压力低于30 GPa时,Al2Ca为脆性相,之后随压力的增大,材料呈延性,增大压力提高了材料的塑性和延展性。态密度计算结果表明:在压力0~50 GPa下,随压力增加,结构稳定性变差,但其结构仍然是稳定的,没有发生相转变。
CASTEP package based on density functional theory was used to calculate the structure, elasticity and electronic properties of Al2Ca phase under different pressures. The calculated lattice parameters of Al2Ca at 0 GPa coincide with the experimental and other theoretical values. The results show that with the increase of pressure, the bulk modulus B, shear modulus G and Young’s modulus E of Al2Ca phase increase, and the hardness of the material increases. When the pressure is lower than 30 GPa, Al2Ca is brittle phase, With the increase of pressure, the material is ductile, increase the pressure to improve the plasticity and ductility of the material. The calculated results of state density show that the structural stability deteriorates with increasing pressure at 0-50 GPa, but the structure is still stable without phase transformation.