Claddings of silicon carbide (SiC)-based composites for light water reactors are expected to be a key component of accident-tolerant fuel technology for enhancing nuclear safety. Muroran Institute of Technology has developed technologies for producing SiC/SiC claddings by a nano-infiltration and transient eutectic phase (NITE) method in the MEXT-funded project named “SCARLET.” As part of this program, neutron irradiation experiments were performed in a pressurized cooling water flow at the Halden Reactor in Norway. During the irradiation experiments, silicon dissolution from the SiC/SiC specimens was measured, and the relationship among the dissolution, properties of SiC/SiC claddings and reactor operating conditions was studied. The morphology of the SiC/SiC claddings was not significantly modified by the irradiation experiments; however, the joint parts were corroded and suffered damage. Observation of irradiated specimens and a rough estimate of the SiC dissolution rate under each irradiation condition indicated that the NITE SiC/SiC composite has potential as a structural material for pressurized water reactors (PWRs) that are operated under hydrogen water chemistry conditions. It is also shown that chemical-vapor-deposited (CVD)-SiC and other coating techniques are necessary for the realization of SiC reactor core. Joining and coating technologies were also tested, but appropriate methods could not be identified experimentally; thus, joining and coating techniques should be further developed.

用于轻水反应堆的碳化硅 (SiC) 基复合材料包壳有望成为提高核安全的容灾燃料技术的关键组成部分。Muroran 技术学院在 MEXT 资助的名为“SCARLET”的项目中开发了通过纳米渗透和瞬态共晶相 (NITE) 方法生产 SiC/SiC 覆层的技术。作为该计划的一部分，在挪威哈尔登反应堆的加压冷却水流中进行了中子辐照实验。在辐照实验过程中，测量了 SiC/SiC 试样中的硅溶解，并研究了溶解、SiC/SiC 包壳性能和反应器运行条件之间的关系。辐照实验未显着改变 SiC/SiC 包覆层的形貌；然而，接头部分被腐蚀和损坏。对辐照样品的观察和对每种辐照条件下 SiC 溶解速率的粗略估计表明，NITE SiC/SiC 复合材料具有作为在氢水化学条件下运行的压水反应堆 (PWR) 结构材料的潜力。还表明化学气相沉积 (CVD)-SiC 和其他涂层技术对于实现 SiC 反应堆堆芯是必要的。还测试了连接和涂层技术，但无法通过实验确定合适的方法；因此，连接和涂层技术应进一步发展。对辐照样品的观察和对每种辐照条件下 SiC 溶解速率的粗略估计表明，NITE SiC/SiC 复合材料具有作为在氢水化学条件下运行的压水反应堆 (PWR) 结构材料的潜力。还表明化学气相沉积 (CVD)-SiC 和其他涂层技术对于实现 SiC 反应堆堆芯是必要的。还测试了连接和涂层技术，但无法通过实验确定合适的方法；因此，连接和涂层技术应进一步发展。对辐照样品的观察和对每种辐照条件下 SiC 溶解速率的粗略估计表明，NITE SiC/SiC 复合材料具有作为在氢水化学条件下运行的压水反应堆 (PWR) 结构材料的潜力。还表明化学气相沉积 (CVD)-SiC 和其他涂层技术对于实现 SiC 反应堆堆芯是必要的。还测试了连接和涂层技术，但无法通过实验确定合适的方法；因此，连接和涂层技术应进一步发展。还表明化学气相沉积 (CVD)-SiC 和其他涂层技术对于实现 SiC 反应堆堆芯是必要的。还测试了连接和涂层技术，但无法通过实验确定合适的方法；因此，连接和涂层技术应进一步发展。还表明化学气相沉积 (CVD)-SiC 和其他涂层技术对于实现 SiC 反应堆堆芯是必要的。还测试了连接和涂层技术，但无法通过实验确定合适的方法；因此，连接和涂层技术应进一步发展。