Single Crystal Growth by Solid State Reaction Synthesis: Informatics Driven Microstructural Analysis and Design

非技术描述：本研究探索了一类新的陶瓷的合成，结构和性能，即由金属和非金属元素组成的化合物。陶瓷单晶材料由于其独特的性质而令人期望，其中原子排列在整个块体样品中是相同的。不幸的是，它们通常很难制造，需要专门的设备和非常高的温度。该项目探索了一种新的固态方法来生长单晶陶瓷，从两种不同陶瓷成分的混合物开始。潜在的存在，为下一代结构和电子应用发现新的和有趣的性能的陶瓷晶体。 此外，相反的过程，即，可以利用从单一材料到两种不同材料的变化来产生复合材料，所述复合材料是不同陶瓷或金属和陶瓷的微观混合物。可以定制这些混合物的规模和互连性以改变整体物理性质。学生正在接受先进技术的培训，包括实验和计算材料科学。他们通常会在高科技行业或政府/工业实验室找到工作。相关的外联活动旨在鼓励K-12学生从事科学和工程职业，特别强调代表性不足的群体。这些努力包括创建双语教育模块，以及参与以下方案：1）高中学生和教师的材料营地，2）选择（绘制工程和科学职业的前景和机会），目标是中学女生，以及3）星星（准备好的学生），其目标是经济和学术上处于不利地位和/或有风险的8至12年级学生。 技术特性：熵稳定氧化物是一种复杂的陶瓷，只有在一定的临界温度以上才稳定。迄今为止，这类材料很少受到研究界的关注。最近观察到一种新的类型的转变，其中大块单晶生长诱导固态合成，开始与两相，多晶前体。相反，这些材料在低于临界温度退火时的类共晶转变产生了新颖的两相形态。该项目结合了实验和基于信息学的建模方法，以寻求对转化机制的基本理解。特别是，该研究旨在确定材料的参数，这些参数与初始微观结构一起定义了所得结构的形态和纹理演变。研究生和本科生正在接受最先进的高温材料合成和表征技术以及成核和生长过程建模的培训。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

NON-TECHNICAL DESCRIPTION: This research explores the synthesis, structure, and properties of a new class of ceramics, i.e. compounds composed of metallic and non-metallic elements. Ceramic single crystal materials, where the atomic arrangement is the same throughout the bulk sample, are desirable because of their unique properties. Unfortunately, they are usually difficult to fabricate, requiring specialized equipment and very high temperatures. This project explores a novel solid-state method for growing a single crystal ceramic, starting from a mixture of two different ceramic compositions. The potential exists for the discovery of ceramic crystals with new and interesting properties for next generation structural and electronic applications. Furthermore, the reverse process, i.e., changing from a single material to two distinct materials can be exploited to create composite materials that are microscopic mixtures of either different ceramics, or a metal and a ceramic. The scale and interconnectivity of these mixtures can be tailored to modify the overall physical properties. Students are undergoing training in advanced techniques encompassing both experimental and computational materials science. They will typically find employment in high tech industries or government/industrial laboratories. Associated outreach activities are directed towards encouraging K-12 students to pursue careers in science and engineering, with a particular emphasis on underrepresented groups. These efforts include the creation of bilingual educational modules, as well as participation in programs such as: 1) Materials Camps for high school students and teachers, 2) CHOICES (Charting Horizons and Opportunities In Careers in Engineering and Science), which is aimed at middle school girls, and 3) STAR (Students That Are Ready), which targets economically and academically disadvantaged and/or at-risk 8th to 12th grade students. TECHNICAL DETAILS: Entropy-stabilized oxides are complex ceramics that are stable only above a certain critical temperature. To date, this material class has received little prior attention from the research community. Recently a new type of transformation was observed whereby bulk single crystal growth was induced by solid state synthesis, starting with a two-phase, polycrystalline precursor. Conversely, the eutectoid-like transformation of these materials when annealed below the critical temperature yields novel two-phase morphologies. The project combines experiment and an informatics-based modelling approach to seek a fundamental understanding of the transformation mechanisms. In particular, the research aims to identify the materials' parameters that together with the initial microstructure, define the morphological and textural evolution of the resultant structure. Graduate students and undergraduates are being trained in state-of-the art high temperature materials synthesis and characterization techniques, as well as modelling of nucleation and growth processes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.