Enabling sustainable fusion and other power generation technologies by novel manufacturing

在国家范围内提供零碳能源的民用聚变发电概念正在成熟，英国通过其新颖的球形托卡马克能源生产(STEP)概念处于领先地位。STEP要求钨反应堆涂层为铜和钢基等离子组件提供关键保护，因为没有其他材料可以提供钨混合物的热物理性能，包括无法避免的高熔点、高导热和抗等离子侵蚀性能。然而，在铜或钢反应堆容器上制备厚钨涂层面临着熔点和热膨胀系数的巨大差异的挑战，这导致了严重的热膨胀失配应变和制造过程中的过早失效，以及不可避免的在役热波动。目前的钨涂层制造工艺无法生产出足够厚度(数毫米)和使用寿命(3年)的涂层以满足可持续的商业应用。该项目将通过研究基于3D打印(3DP)和其他方法的新工作流程来解决制造挑战，以产生基于粉末的梯度涂层，然后是现场辅助烧结(FAST)。FAST是一种先进的快速粉末固化技术。虽然适用于W涂层，但新方法将适用于清洁能源解决方案的一系列具有重要技术意义的不同涂层/基材系统。其创新之处在于几个相互关联的领域：-3DP具有具有地形图案的衬底表面，不浪费金属粉末，通过引入受控的微裂纹来控制应变释放；-在钢和钨之间使用多材料中间层，包括复杂的几何形状和/或瞬时液体相烧结材料；-作为快速工作流程的一个组成部分，有效地对打印的三维多结构进行聚合物脱脂；-对潜在物理过程进行过程模拟，包括应力和应变的演变、裂纹和失效模式，以及新型多材料结构的详细微观结构表征；以及-访问专用等离子反应堆模拟器，以在真实条件下测试和优化涂层和部件。我们的目标是开发新的能力和相关的理解，为聚变和其他低碳电力应用的定制涂层系统生产一个通用的制造平台。总体项目目标是：-开发一种新的、可扩展的制造流程，用于在包括钢和CuCrZr合金在内的一系列聚变能源应用材料上制造毫米级钨涂层；-将该方法扩展到具有复杂几何形状的曲面和结构部件；-制造用于聚变应用的工业规模演示组件。该项目将持续整个聚变CDT学生时代，并建立在我们在过去10年中积累的关于连接不同材料的研究知识的基础上。它还将与牛津大学材料部内的聚变研究机构建立更广泛的联系。该项目属于EPSRC制造未来和核聚变研究领域。该项目是与德国Fritsch博士合作的，该公司是一家先进的机器和材料制造商。

Civil fusion power concepts that offer zero carbon energy at nation-scale are maturing, and the UK has a leading position through its novel Spherical Tokamak for Energy Production (STEP) concept. STEP requires tungsten reactor coatings to provide a critical protection for copper and steel-based plasma facing components because no other material can offer tungsten mix of thermophysical properties, including high melting point, high thermal conductivity and erosion resistance to plasma strikes that cannot be avoided. However, fabrication of thick tungsten coatings on copper or steel reactor vessel is challenged by the large difference in their melting points and thermal expansion coefficients that leads to severe thermal expansion mismatch strains and premature failure during manufacture and inevitable in-service thermal fluctuations. Current tungsten coating manufacturing routes cannot produce coatings of sufficient thickness (multi-millimetre) and lifetime (> 3 years) for sustainable commercial applications.This project will address the manufacturing challenges by researching a new workflow based on 3D printing (3DP) and other approaches to create powder-based graded layers, followed by field assisted sintering (FAST). FAST is an advanced rapid powder consolidation technique. Although applied for W coatings, the new approach will be applicable to a wide range of technologically important dissimilar coating/substrate systems for clean energy solutions. The novelty lies in several interlinked areas:- 3DP with topographically patterned substrate surfaces, with no waste of metallic powders, for controlled strain relief by introducing regulated micro-cracking;- Use of multi-material interlayers between steel and W layers, including complex geometries and/or a transitory liquid phase sintering material;- Technology for effective polymer debinding of printed 3D multi-structures as an integrated part of the FAST workflow;- Process simulations of the underlying physics including the evolution of stresses and strains, cracking and failure modes, and detailed microstructural characterisation of the novel multi-material structures; and- Access to specialised plasma reactor simulators to test and optimise coatings and components under realistic conditions. We aim to develop new capabilities and exploit the associated understanding to produce a generic manufacturing platform for tailored coatings systems for fusion and other low carbon power applications.The overall project objectives are:- To develop a new, scalable manufacturing process workflow for the fabrication of mm-scale tungsten coating on a range of materials for fusion energy applications, including steels and CuCrZr alloys;- To extend the methodology to curved surfaces and structural components with complex geometry;- To fabricate industrial scale demonstrator components for fusion applications.The project will last the length of a fusion CDT studentship and build on the research knowledge we have accumulated over the last 10 years on joining dissimilar materials. It will also link more broadly with the body of fusion research within the Department of Materials , Oxford. This project falls within the EPSRC manufacturing the future and nuclear fusion research area. The project is in collaboration with Dr. Fritsch (Germany), which is an advance machines and materials manufacturer.