Analysis of possible deformation mechanisms in helium–ion irradiated SiC
Analysis of possible deformation mechanisms in helium–ion irradiated SiC
复制标题
DOI：
10.1016/s0022-3115(02)01058-9
复制
发表时间：
2002-12
影响因子：
3.1
通讯作者：
S. Nogami;S. Ohtsuka;M. Toloczko;A. Hasegawa;K. Abe
中科院分区：
文献类型：
--
作者：
S. Nogami;S. Ohtsuka;M. Toloczko;A. Hasegawa;K. Abe
使用有限元模型研究了 He 离子辐照（~2×1022He/m2，低于 200 °C）期间 SiC 物理约束膨胀过程中可能的适应变形模式。当仅通过弹性变形来调节变形时，计算出的内应力远高于 SiC 的断裂应力。另一方面，当允许辐照增强蠕变 (IEC) 作为附加调节机制时，会产生低于断裂应力的应力。对于 SiC 的稳态 IEC 合规系数等于 6×10−5MPa−1dpa−1，观察到的最大 von Mises 应力小于材料的断裂应力。该蠕变柔量值似乎明显大于公开文献中晶体 SiC 的少数实验可用测量值。
Possible modes of accommodating deformation during physically constrained swelling of SiC during He–ion irradiation (∼2×1022He/m2below 200 °C) were studied using finite element modeling. When accommodating deformation occurs only by elastic deformation, calculated internal stresses are much higher than the fracture stress for SiC. On the other hand, stresses below the fracture stress result when allowing irradiation-enhanced creep (IEC) to act as an additional accommodation mechanism. For a steady-state IEC compliance coefficient for SiC equal to 6×10−5MPa−1dpa−1, the maximum observed von Mises stress was less than the fracture stress of the material. This value for the creep compliance appears to be significantly larger than the few experimentally available measured values for crystalline SiC in the open literature.