In this work, we have performed neutron irradiation and sub-sequent microstructural and micro-hardness measurements on a series of tungsten grades. The neutron irradiation was performed in BR2 reactor up to 0.2 dpa at 600, 800 and 1200 °C. The selected irradiation temperatures correspond to a large range of the operation of tungsten in ITER as armour for the divertor. The applied fast neutron flux is representative of ITER irradiation conditions in terms of damage rate. The primary purpose of the study was to establish the relation between the initial microstructure, the resulting irradiation-induced microstructure and corresponding irradiation hardening. The microstructure was studied using transmission electron microscopy (TEM) and hardening was assessed by micro-hardness measurements. The obtained TEM results were used to predict the hardening employing the dispersed barrier model and strength coefficients established for the single crystal from the open literature. Based on the performed analysis, it appeared that the main contribution to the hardening at high irradiation temperature originates from the voids, while the dislocation loops provide a comparable contribution (30–50%) only under irradiation at 600 °C. Excellent agreement between the model prediction and experimentally measured hardness increase was obtained for the single crystal and ITER specification grade without any additional adjustment, while the hardening induced in the cold rolled plate was essentially overestimated by the model. This result suggests that the cold rolled tungsten plate exhibits an alternative mechanisms of the plastic deformation besides the conventional dislocation glide and multiplication, and this alternative mechanism is impacted by the irradiation less severely compared to the prediction coming from the dispersed barrier model.

在这项工作中，我们对一系列钨牌号进行了中子辐照以及随后的显微组织和显微硬度测量。中子辐照是在600、800和1200°C的BR2反应器中进行的，最高可达0.2 dpa。选定的辐照温度对应于ITER中钨的大范围操作，作为分光镜的铠装。就损伤率而言，所施加的快速中子通量代表了ITER辐照条件。该研究的主要目的是建立初始微观结构，由此产生的辐照诱导的微观结构与相应的辐照硬化之间的关系。使用透射电子显微镜（TEM）研究了微观结构，并通过显微硬度测量评估了硬化。所获得的TEM结果用于使用分散的势垒模型和从公开文献中为单晶建立的强度系数来预测硬化。根据进行的分析，似乎是在高辐照温度下对硬化的主要贡献来自空隙，而位错环仅在600°C辐照下才提供可比的贡献（30–50％）。单晶和ITER规格等级的模型预测与实验测得的硬度增加之间具有极好的一致性，而无需进行任何其他调整，而该模型实际上高估了冷轧板中引起的硬化。