Microstructural characterization and calculation of how several intrinsic features contribute to the mechanical properties of highly strained Inconel X-750 alloy specimens irradiated to 84 dpa at two distinct temperature ranges (300 °C–330 °C and 120 °C–280 °C) were performed. The individual contributions of different microstructural features to the critical resolved shear stress (CRSS) of the material, including the γ matrix, γ′ precipitates, irradiation induced defects, and helium bubbles, were calculated. The obstacle strength of He bubbles was found to be size-dependent and a critical size was determined. For bubbles < 2.4 nm, the obstacle strength is only approximately 0.03 while it can be as high as 0.55 for bubbles > 6.6 nm. In the high temperature range (300–330 °C) irradiated specimen, localised dislocation slip was found responsible for the failure of the specimen during micro-tensile testing, associated with significant helium bubble elongation. Elongation of helium bubbles on both the primary and adjacent secondary {1 1 1} planes was likely induced by the cross slip of screw dislocations. Nanotwins were also found adjacent to the shear failure surface in the high temperature specimen, but no elongated bubbles were found within the nano-twinned region. In the low temperature range (120–280 °C) irradiated highly strained specimen, a dislocation network structure was revealed.

在两个不同温度范围（300 °C–330 °C 和 120 °C–280 °C）下辐照至 84 dpa 的高应变 Inconel X-750 合金试样的机械性能的显微结构表征和计算是执行。计算了不同微观结构特征对材料临界分辨剪切应力 (CRSS) 的单独贡献，包括 γ 基体、γ' 沉淀物、辐射诱导缺陷和氦气泡。发现 He 气泡的障碍强度与尺寸有关，并确定了临界尺寸。对于 < 2.4 nm 的气泡，障碍强度仅约为 0.03，而对于 > 6.6 nm 的气泡，障碍强度可高达 0.55。在高温范围（300-330°C）辐照样品中，发现局部位错滑移是微拉伸试验期间试样失效的原因，与显着的氦泡伸长有关。初级和相邻次级上的氦气泡的伸长率 {1 1  1} 平面可能是由螺位错的交叉滑移引起的。在高温试样的剪切破坏表面附近也发现了纳米孪晶，但在纳米孪晶区域内没有发现细长气泡。在低温范围 (120–280 °C) 辐照的高应变试样中，揭示了位错网络结构。