Development of Crack Growth Rate SCC Devices for Testing in Super Critical Water (SCW) Environment

A detailed investigation of detrimental processes such as corrosion and stress corrosion cracking (SCC), ageing embrittlement, creep and fatigue etc., which may significantly affect the materials performance in specific water chemistry environments, is of fundamental importance for the development of the Supercritical Water (SCW) reactor concept. In particular, SCC crack growth rate testing is difficult to perform due to complex requirements for the experimental facilities which include water chemistry loops equipped with relevant pH, conductivity, dissolved O2 and H2 sensors, autoclaves with mechanical loading devices, incorporating crack growth rate measurement by direct current potential drop (DCPD) and displacement measurement by linear variable differential transducers (LVDT). All these requirements significantly advance the total materials qualification costs. JRC in cooperation with VTT has been working on a new type of loading devices which are expected to decrease these costs and at the same time guarantee enough reliability and flexibility for both SCC and future irradiation assisted stress corrosion cracking (IASCC) testing to be performed in SCW environments. This paper summarizes the first results of SCC crack growth rate measurements in SCW by using a pneumatic bellows based loading device developed in the frame of JRC-VTT cooperation. Furthermore, the results of crack growth rates in SCW (550oC, 8000 ppb of dosed oxygen) are compared to those measured by using the same loading device in 288oC subcritical water. Finally, the development of another miniature size autoclave concept together with preliminary results obtained from it is described in detail.

NOVOTNY Radek;  MOILANEN P;  HAEHNER Peter;  SIEGL J;  HAUSILD P; 

2014-01-02

China Guangdong Nuclear Power Holding Co., Ltd (CGNPC)

JRC86797

https://publications.jrc.ec.europa.eu/repository/handle/JRC86797,