Investigating the microstructure and mechanical behaviour of simulant "lava-like" fuel containing materials from the Chernobyl reactor unit 4 meltdown
Investigating the microstructure and mechanical behaviour of simulant "lava-like" fuel containing materials from the Chernobyl reactor unit 4 meltdown
复制标题
研究含有切尔诺贝利反应堆 4 号反应堆熔毁材料的模拟“熔岩类”燃料的微观结构和机械行为
DOI：
10.1016/j.matdes.2021.109502
复制
发表时间：
2021
影响因子：
8.4
通讯作者：
Paraskevoulakos C
中科院分区：
文献类型：
--
作者：
Paraskevoulakos C
关闭受损的切尔诺贝利核反应堆4号机组是国际社会的一个最高优先事项。在此类操作开始之前，了解事故期间形成的危险材料的行为至关重要。由于这些材料是在极端和大多数无法量化的条件下形成的，仅凭建模不足以准确预测其物理、化学和主要是机械行为。与此同时，在使用机器人系统进行检索之前，首先要了解这些材料的机械特性，例如其强度，而预期从它们施加的力是关键的设计问题之一。在本文中，我们的目标是通过测试小规模，低放射性模拟物的标准机械性能的测量过程中形成的事故。采用赫兹压痕、同步加速器X射线断层扫描和数字体积相关（DVC）的组合方法来估计力学性能。位移场周围的赫兹压痕，在同步加速器中进行原位，测量分析断层图像与DVC。在压痕过程中施加的负载，结合全场位移测量DVC被用来估计这些危险材料的力学性能，如杨氏模量和泊松比。
Decommissioning of the damaged Chernobyl nuclear reactor Unit 4 is a top priority for the global community. Before such operations begin, it is crucial to understand the behaviour of the hazardous materials formed during the accident. Since those materials formed under extreme and mostly unquantified conditions, modelling alone is insufficient to accurately predict their physical, chemical and, predominantly, mechanical behaviour. Meanwhile, knowledge of the mechanical characteristics of those materials, such as their strength, is a priority before robotic systems are employed for retrieval and the force expected from them to be exerted is one of the key design questions. In this paper we target to measurement of the standard mechanical properties of the materials formed during the accident by testing small-scale, low radioactivity simulants. A combined methodology using Hertzian indentation, synchrotron X-ray tomography and digital volume correlation (DVC), was adopted to estimate the mechanical properties. Displacement fields around the Hertzian indentation, performed in-situ in a synchrotron, were measured by analysing tomograms with DVC. The load applied during the indentation, combined with full-field displacement measured by DVC was used to estimate the mechanical properties, such as Young's modulus and Poisson's ratio of these hazardous materials.