Void denuded zone formations under electron irradiation in austenitic stainless steels modified with oversized elements

Sekio, Yoshihiro  ; Yamashita, Shinichiro   ; Sakaguchi, Norihito*; Takahashi, Heishichiro

To predict the changes of vacancy diffusivity and concentration in alloys with additional elements to those in the based alloy from the experimentally obtained widths of void denuded zone (VDZ) formations induced during irradiations near grain boundaries, the effects of oversized additional elements of V and Zr on VDZ widths were evaluated in the electron-irradiated SUS316L and the modified type SUS316L steels with V and Zr. These steels were electron-irradiated at the temperature of 450C. The results showed that the VDZ widths were 116nm, 95nm and almost zero in the SUS316L, the SUS316L-V and SUS316L-Zr steels respectively. The addition of V and Zr elements would have a role to decreasing the VDZ widths as results of the decrease of vacancy diffusivity in matrix under irradiations. In particular, the lesser VDZ width induced in the SUS316L-Zr would be also affected by the effective vacancy concentration.