Small punch creep (SPC) testing represents an effective way to rapidly assess the creep performance of novel materials and potentially monitor degradation of in-service components. Recent progress in standardisation has also led to improvements in data analysis. However, estimation of equivalent uniaxial stresses is still somewhat challenging and has hindered wider usage of the small punch technique. In this study, the creep properties of two candidate materials for structural applications in future fusion reactors were assessed via SPC. These included the baseline structural material, Eurofer97, and a more recently developed 14Cr Oxide Dispersion Strengthened (ODS) steel (14YWT). Having been assessed at 550 °C, the 14YWT demonstrated superior creep life and significantly lower rates of deformation, but also exhibited reduced ductility. The Modified Chakrabarty (MCH) approach was employed to estimate equivalent uniaxial creep stresses. This methodology appeared to work well with the Eurofer97 but struggled when applied to 14YWT, making accurate estimation of the 14YWT performance difficult. Since the MCH approach was developed for ductile materials, its predictive capabilities may have been limited by the low ductility of 14YWT.

小冲头蠕变 (SPC) 测试代表了一种快速评估新型材料蠕变性能和潜在监测使用中组件退化的有效方法。标准化的最新进展也导致了数据分析的改进。然而，等效单轴应力的估计仍然有些挑战，并且阻碍了小冲压技术的更广泛使用。在这项研究中，通过 SPC 评估了未来聚变反应堆结构应用的两种候选材料的蠕变性能。其中包括基准结构材料 Eurofer97 和最近开发的 14Cr 氧化物弥散强化 (ODS) 钢 (14YWT)。在 550 °C 下进行评估后，14YWT 表现出优异的蠕变寿命和显着较低的变形率，但也表现出较低的延展性。改进的 Chakrabarty (MCH) 方法用于估计等效单轴蠕变应力。这种方法似乎与 Eurofer97 配合得很好，但在应用于 14YWT 时会遇到困难，因此很难准确估计 14YWT 的性能。由于 MCH 方法是为延展性材料开发的，其预测能力可能受到 14YWT 低延展性的限制。