[3D09-12] PWSCC

[3D10] Effect of microstructure on SCC growth behavior of thermal aged SUS630 in high-temperature water

*Takuyo Yamada¹, Kohei Kokutani¹, Toru Oumaya¹, Koji Arioka¹ (1. INSS)

Keywords:SUS630, 17-4 PH stainless steel, thermal aging, stress corrosion cracking (SCC) in high-temperature water, light water reactor

After thermal aging at 320, 350 and 400°C for up to 20,000h of SUS630, the hardness and SCC growth rate are increased with aging time. Microstructure and hydrogen thermal desorption Analysis of thermal aged SUS630 (H1150 and H1100) at 320℃ for 20,000 h were investigated. And then, correlation of the SCC growth behavior, microstructure and hydrogen thermal desorption analysis results. As a result, it seems that the fine Cu-rich phase and G phase were affected on SCC growth behavior. But thsose fine precipitations are not relative to trapsite for hydrogen.