Molecular dynamics simulations are carried out to study the mechanical and elastic properties of single crystal aluminum with various crystal orientations at different temperatures and under different pressure. Transformations of lattice structures under high pressure, tensile and shearing loads are investigated, respectively. When the pressure increases to 10¹¹ Pa, the face centered cubic (FCC) structure is completely transformed into body centered cubic (BCC) and other structures. The transformation from FCC to hexagonal close packed (HCP) and other structures takes place during tensile and shearing processes. Elastic compliance constants are calculated at different temperatures. Elastic modulus and shear modulus of different crystal orientations at different temperatures are calculated by the formula method, and compared with the results of molecular dynamics method. The decrease extent of elastic modulus in <111> crystal orientation is the smallest with the increase of temperature. The effects of high pressure on elastic modulus and shear modulus in different crystal orientations are also investigated. When the pressure exceeds 10⁹ Pa, the elastic modulus and shear modulus in all crystal orientations begin to increase. Poisson's ratio in different crystal orientations at different temperatures and under high pressure are also calculated.

中文翻译：

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温度和压力对不同晶向的单晶铝弹性性能的影响

进行了分子动力学模拟，以研究在不同温度和压力下具有不同晶体取向的单晶铝的力学和弹性性能。分别研究了在高压，拉伸和剪切载荷下晶格结构的转变。当压力增加到10 ¹¹Pa，面心立方（FCC）结构完全转换为体心立方（BCC）和其他结构。从FCC到六方密堆积（HCP）和其他结构的转变发生在拉伸和剪切过程中。弹性柔量常数是在不同温度下计算的。采用公式法计算了不同温度下不同晶体取向的弹性模量和剪切模量，并与分子动力学方法的结果进行了比较。<111>晶体取向的弹性模量的降低程度随温度的升高而最小。还研究了高压对不同晶体取向下的弹性模量和剪切模量的影响。当压力超过10 ⁹Pa，所有晶体取向的弹性模量和剪切模量开始增加。还计算了在不同温度和高压下不同晶体取向下的泊松比。