Enabling sustainable fusion and other power generation technologies by novel manufacturing

在全国范围内提供零碳能源的民用核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要求钨反应器涂层为铜和钢基等离子体组件提供关键的保护，因为没有其他材料可以提供钨混合物的热物理性能，包括高熔点、高导热性和抗等离子体冲击的耐蚀性。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差异较大的挑战，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使用过程中的热波动。目前的钨涂层制造路线无法生产足够厚度（多毫米）和寿命（50 - 30年）的涂层，无法实现可持续的商业应用。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，以创建基于粉末的分级层，然后是现场辅助烧结（FAST）。FAST是一种先进的粉末快速固结技术。虽然应用于W涂层，但新方法将适用于清洁能源解决方案的各种技术重要的不同涂层/基材系统。新颖之处在于几个相互关联的领域：- 3d打印与地形图案的基底表面，没有金属粉末的浪费，通过引入调节微裂纹来控制应变缓解；-在钢层和钨层之间使用多种材料夹层，包括复杂的几何形状和/或过渡液相烧结材料；-打印3D多结构的有效聚合物脱粘技术，作为FAST工作流程的组成部分；-基础物理过程模拟，包括应力和应变的演变，开裂和破坏模式，以及新型多材料结构的详细微观结构特征；-使用专门的等离子体反应器模拟器，在现实条件下测试和优化涂层和组件。我们的目标是开发新的能力，并利用相关的知识来生产一个通用的制造平台，为聚变和其他低碳电力应用量身定制涂层系统。项目总体目标是：-开发一种新的、可扩展的制造工艺流程，用于在一系列聚变能应用材料上制造毫米级钨涂层，包括钢和CuCrZr合金；-将方法扩展到曲面和具有复杂几何形状的结构部件；-为核聚变应用制造工业规模的示范组件。该项目将持续一个融合CDT学生的时间，并以我们过去10年在连接不同材料方面积累的研究知识为基础。它还将与牛津大学材料系内的核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Dr. Fritsch（德国）合作的，这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.