Vacancy Engineered Rare Earth Oxide Coatings for High Temperature Applications

钢通常在各种各样的应用中用作结构合金，包括家用电器，餐具以及发电和石油和天然气管道中的组件。 然而，由于水垢的存在，所选钢在高温状态下的耐腐蚀性和耐失效性较差。 在钢中添加稀土可提高抗氧化性，导致生产成本高。 然而，表面稀土氧化物涂层的应用可能会提供一个特定的解决方案的问题。 该研究将使我们能够开发用于钢基体高温保护的空位工程氧化铈涂层。 该提案的主要目标是：（1）铈氧化物的制备，（2）比较纳米晶二氧化铈和二氧化钛的有效性以比较混合价态在氧化动力学中的作用，（3）制备并研究La和Nd掺杂的二氧化铈作为氧空位浓度的函数对高温保护功效的作用，（4）解释了氧化动力学与空位浓度的关系，并对掺杂和未掺杂的氧化铈的本质有了更基本的了解。 作为该计划的一部分，将对两种混合价态材料（氧化铈和氧化钛纳米颗粒）对钢的高温氧化保护性质进行比较研究。 这些稀土涂层的基本考虑和研究也将导致氧化动力学作为氧空位和混合价态的函数的理解。 因此，这些结果将导致更好的和成本效益的抗氧化涂层的钢材料的设计。

Steels are often used as structural alloys in a wide variety of applications including household appliances, cutlery, and components in power generation and oil and gas pipelines. However, select steels are not as corrosion and failure resistant in the high temperature regime, due to scale spallation. Addition of rare earths in the steel can increase the oxidation resistance, resulting high production cost. However, the application of superficial rare earth oxide coatings might provide a particular solution to the problem. The research would allow us to develop vacancy engineered cerium oxide coatings for high temperature protection of steel substrates. The main objectives of the proposal are: (1) Preparation of cerium oxides, (2) Compare the effectiveness of nanocrystalline ceria and titania to compare the effect of mixed valence states in the oxidation kinetics, (3) Prepare and study the effect of La and Nd doped ceria as a function of oxygen vacancy concentration on the efficacy of the high temperature protection, (4) Explain the oxidation kinetics as a function of vacancy concentration in the formation of early chromia healing layer.A more fundamental understanding of the true nature of cerium oxide with or without doping will be investigated. Comparative studies of two mixed valence states materials (cerium oxide and titanium oxide nanoparticles) on the protective nature of the steel from high temperature oxidation will be conducted as part of this program. This basic consideration and study of these rare earth coatings will also lead to the understanding of the oxidation kinetics as a function of oxygen vacancies and mixed valence states. Thus, these results will lead to the design of better and cost effective oxidation resistant coatings for steel materials.