Significant progress in many classes of materials could be made with the availability of experimentally-derived large datasets composed of atomic identities and three-dimensional coordinates. Methods for visualizing the local atomic structure, such as atom probe tomography (APT), which routinely generate datasets comprised of millions of atoms, are an important step in realizing this goal. However, state-of-the-art APT instruments generate noisy and sparse datasets that provide information about elemental type, but obscure atomic structures, thus limiting their subsequent value for materials discovery. The application of a materials fingerprinting process, a machine learning algorithm coupled with topological data analysis, provides an avenue by which here-to-fore unprecedented structural information can be extracted from an APT dataset. As a proof of concept, the material fingerprint is applied to high-entropy alloy APT datasets containing body-centered cubic (BCC) and face-centered cubic (FCC) crystal structures. A local atomic configuration centered on an arbitrary atom is assigned a topological descriptor, with which it can be characterized as a BCC or FCC lattice with near perfect accuracy, despite the inherent noise in the dataset. This successful identification of a fingerprint is a crucial first step in the development of algorithms which can extract more nuanced information, such as chemical ordering, from existing datasets of complex materials.
翻译:由原子特性和三维坐标组成的实验性大型数据集的提供,可以在许多材料类别中取得重大进展; 由原子特性和三维坐标组成的实验性大型数据集的提供,可以在许多材料类别中取得重大进展; 直观当地原子结构,例如原子探测器断层仪(APT),定期生成由数百万原子组成的数据集,这是实现这一目标的一个重要步骤; 然而,先进的APT仪器产生噪音和稀少的数据集,提供关于元素类型、但模糊的原子结构的信息,从而限制其随后对材料发现的价值; 应用材料指纹鉴定程序,即机器学习算法,加上地形数据分析,提供了从ATT数据集中提取从这里到前面的前所未有的结构信息的途径; 作为概念的证明,材料指纹应用于含有高持久性聚层聚物合金(ABC)和面中心立立立岩晶体结构的高密度数据集。 本地原子配置以任意性原子标定,可以将其描述为一种上层描述为BCC或FCC 立方体结构结构信息的从这里提取前所未有的结构信息,而这种精度的精度的精度的精度是目前最精确的精确的序列数据。