Abstract Sv 07Kh25N13 is austenitic stainless steel used in nuclear industry. Due to its excellent corrosion resistance in the environment of WWER type nuclear reactor primary circuit, it is applied as anticorrosive cladding of the reactor pressure vessel. In this paper, results of detailed experimental research of failure behaviour of the cladding are presented. Static fracture toughness values J0.2 exhibited an extreme scatter. Metallographic analysis performed on the fractured specimens revealed large variations of structure within every single cladding layer. Fractographic analysis performed on fracture surfaces revealed considerable variations of micromechanisms taking place during ductile crack propagation. Conclusions on the relationship between the local microstructure, the failure mode and the fracture toughness of the cladding were drawn. Results indicate that the fracture toughness of the cladding was primarily determined by local amount of sigma phase in the area of crack propagation.

中文翻译：

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sv 07Kh25N13奥氏体不锈钢熔覆层失效行为

摘要 Sv 07Kh25N13 是用于核工业的奥氏体不锈钢。由于其在WWER型核反应堆一回路环境中具有优异的耐腐蚀性能，被用作反应堆压力容器的防腐包层。在本文中，介绍了包层失效行为的详细实验研究结果。静态断裂韧性值 J0.2 表现出极大的分散性。对断裂试样进行的金相分析表明，每个包层内的结构都有很大的变化。在断裂表面上进行的断口分析揭示了在延性裂纹扩展过程中发生的微观机制的相当大的变化。得出了局部显微组织、破坏模式和熔覆层断裂韧性之间关系的结论。