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晶体弹性是材料的基本属性,是材料科学、固体物理、固体化学,以及地质科学等研究领域中的重要考虑因素。由于单晶弹性常数的实验测量比较困难,在数万种无机晶体中只有约1%的晶体的单晶弹性常数是已知的,因此经常需要从理论上计算晶体弹性。我们基于从应变到应力空间的映射,设计开发了新的单晶弹性常数算法与软件。与此前的算法相比,新算法的计算效率高,普适性好。我们在此基础上通过海量计算建立了晶体弹性数据库,并陆续收集了已知的实验数据。以材料的硬度为例,通过数据库进行数据挖掘,揭示了最软弹性形变模式控制材料硬度的“木桶效应”。论文还展示了这一木桶效应在材料设计中的应用。结果表明,通过氮或铼的合金化强化最软的弹性模式,可以进一步提高这种硬质材料的硬度。
Crystal elasticity is a fundamental property of materials and is an important consideration in the fields of material science, solid state physics, solid chemistry, and geosciences. Since experimental measurements of the single crystal elastic constants are difficult, only about 1% of the crystals in tens of thousands of inorganic crystals have known single crystal elastic constants, and therefore it is often necessary to calculate the crystal elasticity theoretically. Based on the mapping from strain to stress space, we developed a new single-crystal elastic constant algorithm and software. Compared with the previous algorithm, the new algorithm has high computational efficiency and good universality. Based on this, we established a crystal elasticity database through massive calculation, and gradually collected known experimental data. Take the hardness of the material as an example, data mining through the database reveals the “barrel effect” that controls the hardness of the material with the softest elastic deformation mode. The paper also shows the application of this barrel effect in material design. The results show that the hardness of this hard material can be further increased by alloying the nitrogen or rhenium to strengthen the softest elastic mode.