Materials Chemistry Applications that Support the Nuclear Industry

拟议的研究旨在支持核工业在应用热力学，高温材料化学和高温水化学的研究领域。已经确定，从处理黄饼、设计新燃料、下一代核反应堆到乏燃料的废物处理，与燃料循环的各个方面都存在材料化学问题。尽管在开发用于描述燃料在各种环境（即气体、水）中的行为的热力学模型方面取得了进展，但问题仍然存在，而且随着21世纪生产对环境负责的能源形式的需求增加，找到这些问题的解决方案至关重要。***高温材料的基本工具之一是相图和相图评价。提出的研究将建立在主要研究者的背景下，应用热力学相图建模感兴趣的系统。PI先前的工作模拟了已知在燃烧燃料中形成的各种金属合金系统。众所周知，Pd-Sn-Sb-Te的四元体系和三元Pd-Ag-Cd在事故场景中是重要的：传热回路中气溶胶中的四元体系和控制棒的三元体系。同样，还有其他金属合金系统可能是下一代反应堆中合适的液体冷却剂。***在拟议的新燃料领域，碳化铀和氮化物显示出潜力，但不像UO2那样被充分了解。此外，用钍代替铀（或两者同时使用）可能会令人感兴趣。了解这些系统的行为方式是将它们开发成燃料的第一步，对于考虑事故情况也很重要。***正在提出一个多年和多方面的方法，继续在安大略理工大学使用x射线衍射（XRD），差热分析（DTA）和其他方法进行实验工作。作为PI和CNL，与加拿大核实验室（Chalk River）的持续合作有着悠久的历史。在国际上，PI与欧洲的主要研究机构（例如，CEA、ITU和IRSN）建立了联系。这就有可能在共同感兴趣的领域与这些伙伴一起进行实验性工作。***与联合理工大学的同事合作，计划研究拟议的燃料处置方法。燃料模型虽然是为高温行为而开发的，但可以适用于水环境（例如，储存舱）或拟议的地下埋藏环境。这项工作也有助于研究各种核应用中的腐蚀。总之，这项工作将加强在UOIT（或其他地方）进行的实验工作与随后可以开发的热力学和热化学模型之间的联系

The proposed research is intended to support the nuclear industry in the research areas of applied thermodynamics, high temperature materials chemistry, and aqueous chemistry at elevated temperatures. It has been established that there are material chemistry issues related to all aspects of the fuel cycle, from processing yellow cake, design of new fuel, the next generation of nuclear reactors, and waste disposal of spent fuel. While progress has been made to develop thermodynamic models for describing the behaviour of fuel in various environments (i.e., gaseous, aqueous) issues remain, and as the need to produce environmentally responsible forms of energy increases in the 21st century, it is essential that solutions to these issues be found.***One of the basic tools for high temperature materials is the phase diagram and phase diagram evaluation. The proposed research will build on the primary investigator's background in applying thermodynamic phase diagram modelling to systems of interest. Previous work by the PI has modelled various metallic alloy systems known to form in burned up fuel. The quaternary system of Pd-Sn-Sb-Te and the ternary Pd-Ag-Cd are known to be important during accident scenarios: the quaternary in aerosols in the heat transfer circuit and the ternary with the control rods. As well, there are other metallic alloy systems that may be suitable liquid coolants in the next generation of reactors.***In the area of proposed new fuels, uranium carbides and nitrides show potential, but are not as well understood as UO2. Further, replacing uranium with thorium (or using both together) may be of interest. Understanding how these systems behave is the first step in developing them into fuel, and is important in considering accident scenarios.***A multi-year and multi-faceted approach is being proposed, continuing experimental work being performed at the University of Ontario Institute of Technology using X-ray Diffraction (XRD), Differential Thermal Analysis (DTA), and other methods. Continuing collaborations with the Canadian Nuclear Labs (Chalk River) as the PI and CNL have a long standing history. Internationally, the PI has developed links to the major research institutions in Europe (e.g., CEA, ITU, and IRSN). This has allowed for the potential to do experimental work in conjunction with these partners in areas of mutual interest.***In collaboration with colleagues at UOIT, studies of proposed disposal methods for fuel are planned. The models for fuel, while developed for high temperature behaviour can be adapted to an aqueous environment (e.g., storage bays) or proposed environments for underground burial. The work also lends itself to studying corrosion in various nuclear applications. In conclusion, this work will strengthen the links between experimental work performed at UOIT (or elsewhere) and the thermodynamic and thermochemical models that can be subsequently developed.**