DMREF/Collaborative Research: Nitride Discovery - Creating the Knowledge Base for Hard Coating Synthesis

在必须保护运动部件免受过度磨损的应用中，通常在部件上应用硬涂层。被称为氮化物的硬陶瓷材料通常用于这些涂层，但氮化物涂层的性能有限且经常不足，导致重要部件的击穿。预测了新型氮化材料的耐磨性和耐腐蚀性将得到显著提高。然而，这些材料的制造仍然是一个挑战。该奖项支持系统地确定制造这些所需新氮化物材料的条件的研究。这项研究的结果将通过有针对性的合成方法加速硬、耐磨和耐腐蚀涂层的发现，为新兴应用提供新的涂层材料，包括节油喷气发动机和燃气轮机、环保无润滑油切削工具、高温聚光太阳能发电厂和风力涡轮机。在这项工作中，设计涂层的方法促进了有前途的新氮化物的引入，因为同时优化成分、微观结构和沉积过程的传统方法过于昂贵和缓慢，所以这些新氮化物尚未得到开发。该方法从热力学和动力学参数出发，通过确定性途径确定工艺参数空间，以获得所需的成分和微观结构，然后进行实验合成。该方法基于实验和密度泛函理论计算的迭代结合，以确定过渡金属氮化物涂层沉积过程中氮的掺入动力学和相形成。研究工作主要集中在涂层合成过程中生长过渡金属氮化层表面的反应和扩散速率以及局部平衡的系统测定。将开发一个定量模型，利用测量值和计算值预测沉积氮化物的组成和相作为入射离子能量学和生长温度和压力的函数。该模型将通过涂层沉积实验进行验证。将探索新的超硬、韧性和空位稳定氮化物相的沉积。本研究收集的数据将通过一个开放的在线数据库公开提供。

In applications where moving parts must be protected from excessive wear, hard coatings are often applied to components. The class of hard ceramic materials known as nitrides are often used for these coatings, but the performance of nitride coatings is limited and often insufficient, leading to breakdown of important components. New nitride materials have been predicted that are expected to have the significantly improved properties for wear resistance and corrosion resistance. Fabrication of these materials, however, remains a challenge. This award supports research to systematically determine the conditions that will enable the manufacture of these desired new nitride materials. The results of this research will accelerate discovery of hard, wear-resistant and corrosion-resistant coatings through a targeted synthesis approach, yielding new coating materials for emerging applications including fuel-efficient jet engines and gas turbines, environmentally-friendly lubricant-free cutting tools, high-temperature concentrating solar power plants, and wind turbines.The coatings-by-design approach in this work facilitates the introduction of promising new nitrides, which have remained unexplored because the traditional approach of simultaneously optimizing composition, microstructure, and deposition process is too costly and slow. This method enables a deterministic pathway to ascertain the processing parameter space to achieve the desired composition and microstructure from thermodynamic and kinetic parameters, and then synthesize the coating experimentally. This method is based on an iterative combination of experiments and density functional theory calculations, to determine nitrogen incorporation kinetics and phase formation during deposition of transition metal nitride coatings. The research effort focuses primarily on the systematic determination of reaction and diffusion rates and local equilibria at the surface of growing transition metal nitride layers during coating synthesis. A quantitative model will be developed that predicts composition and phase of deposited nitrides as a function of incident ion energetics and growth temperature and pressure, using both measured and calculated values. The model will be verified by experimental coating deposition. Deposition of new super-hard, tough, and vacancy-stabilized nitride phases will be explored. Data collected in this research will be made publicly available through an open online database.