Macroscopic properties and microstructure changes of heavily neutron-irradiated β-Si3N4 by annealing
Macroscopic properties and microstructure changes of heavily neutron-irradiated β-Si3N4 by annealing
复制标题
强中子辐照β-Si3N4退火宏观性能及微观结构变化
DOI：
10.1016/s0022-3115(02)01301-6
复制
发表时间：
2002
影响因子：
3.1
通讯作者：
T. Yano
中科院分区：
文献类型：
--
作者：
M. Akiyoshi;K. Ichikawa;T. Donomae;T. Yano
在实验快堆中进行了不同条件下强中子辐照的烧结β-Si3N4样品的膨胀和热扩散率测量。测量了辐照后等时退火至1500℃后这些参数的变化。透射电子显微镜观察表明，许多样品形成了间隙位错环，并在1500℃下退火后比较稳定。在1500℃下退火的样品中出现了气泡。β-Si3N4样品在中子辐照下表现出很小的膨胀，但在1300℃以下的温度下，样品的膨胀很小。热扩散率的恢复率在没有太多位错环的样品中较高。β-Si3N4的热扩散率和宏观长度的退火行为表明，间隙原子至少在380℃左右移动，空位在1100℃左右开始移动。
Swelling and thermal diffusivity measurements have been carried out on sintered β-Si3N4specimens that were heavily neutron-irradiated in an experimental fast reactor under various conditions. Changes in these parameters after post-irradiation isochronal annealing up to 1500 °C were measured. TEM observation showed that interstitial dislocation loops were formed in many specimens, and were stable after annealing at 1500 °C. Bubbles were formed in the specimens annealed at 1500 °C. Neutron-irradiated β-Si3N4showed small swelling that was recovered very slightly due to annealing up to 1300 °C. The specimens showed very small expansion at 1200–1300 °C, which would be caused by He or H2bubble formation. Recovery of the thermal diffusivity is higher in the specimen that did not contain many dislocation loops. The annealing behavior of the thermal diffusivity and macroscopic length in β-Si3N4indicated that interstitial atoms are mobile at least at 380 °C, and vacancies begin to move around 1100 °C.