Finite element modelling of the corrosion of stainless steels/CuCrZr for STEP

STEP 不锈钢/CuCrZr 腐蚀的有限元建模

• 批准号: 2764607
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2764607
• 关键词: Finite; element; modelling; corrosion; stainless

The STEP programme roadmap is very tight, with a need to down select materials in the next few years, before build can begin in 2032, if the programme is to deliver by 2040. There is a need to select the materials that will carry coolant to remove reactor heat, which might be stainless steels, as used in many fission plants, and also proposed for ITER, using boronated coolant water.To achieve the ambitious goals for fusion state-of-the art corrosion modelling capabilities will be needed to support experiments. This project will use phase field approaches embedded in finite element models, being developed at Imperial College, jointly by the Martinez-Paneda and Wenman groups to model corrosion development (including microstructure, electrolyte ion concentrations, pit nucleation and growth and transition to stress corrosion cracks). The work will use either or both the COMSOL and ABAQUS finite element codes. The current models build on the work of Turnbull et al. (2008). that showed that pit growth in stainless steels can be explained by the development of plastic strains at the pit sides that lead to oxide fracture and increase the corrosion rate of the underlying metal. These models have very recently been enhanced further to by addition of electrolyte ion concentrations and thus can be used to model a range of coolant chemistries and then can be further advanced by addition of microstructure via crystal plasticity approaches allowing the effects of localised stress/strains, due to crystal orientation, to be considered in the corrosion process. The models, whilst initially tested on stainless steels can be developed further/adapted to other coolant/materials combinations such as CuCrZr or martensitic/ferritic steels as proposed for STEP.

STEP方案路线图非常紧凑，如果该方案要在2040年之前交付，就需要在2032年开始建设之前，在未来几年减少选择材料。需要选择携带冷却剂的材料来去除反应堆热量，这些材料可能是不锈钢，如许多裂变工厂中使用的，也可能是ITER建议的使用含硼冷却剂的水。为了实现聚变的雄心勃勃的目标，将需要最先进的腐蚀模拟能力来支持实验。该项目将使用嵌入在帝国理工学院由Martinez-Paneda和温曼小组联合开发的有限元模型中的相场方法来模拟腐蚀发展(包括微观结构、电解液离子浓度、孔洞形核和生长以及向应力腐蚀裂纹的过渡)。这项工作将使用COMSOL和ABAQUS有限元程序中的一种或两种。目前的模型建立在特恩布尔等人的工作基础上。(2008年)。这表明，不锈钢中的孔洞生长可以通过孔洞两侧的塑性应变的发展来解释，这些塑性应变导致氧化物断裂，并增加了下层金属的腐蚀速度。最近，通过添加电解液离子浓度，这些模型得到了进一步增强，因此可以用来对一系列冷却剂化学成分进行建模，然后可以通过晶体塑性方法添加微观结构，从而在腐蚀过程中考虑由于晶体取向而产生的局部应力/应变的影响。虽然这些模型最初在不锈钢上进行了测试，但可以进一步开发/适应其他冷却剂/材料组合，如为STEP建议的CuCrZr或马氏体/铁素体钢。