납-비스무스 공융물 환경에서의 적층제조된 재료의 부식 거동 연구

Abstract

This paper study on LBE corrosion behavior of clad material manufactured by direct energy deposition . Fe-12Cr-2Si alloys, which is corrosion resistance material with clad, are immersed in 550 ℃, 1e-7 wt.% dissolved oxygen concentration static LBE. At the same time, SS316L clad are also exposed to same condition. Through a scanning electron microscope, corroded cross-section of clad Fe-12Cr-2Si, clad SS316L and as-received SS316L are compared. The clad Fe-12Cr-2Si shows more enhanced corrosion resistance than as-received Fe-12Cr-2Si because grain size of the clad is bigger so that diffusion paths like grain boundaries decrease. On the other hand, corrosion resistance of the clad SS316L is inferior to as-received SS316L. When passive layer is not sufficient, solub le Ni in LBE is easy to diffuse not only grain boundary but also grain. Larger grain which has high diffusivity along crystal plane locally, deeper the dissolution and LBE penetration depth.