CORROSION RESISTANCE OF REFRACTORY METALS AND CERAMICS IN LEAD-BISMUTH AT 700℃

摘要

Corrosion tests of refractory metals and ceramics were carried out employing high-temperature LBE. Oxygen concentrations in this experiment were 6.8 × 10~(-7) wt.% for ceramics (SiC/SiC composites) and 5 × 10~(-6) wt.% for refractory metals (W, Mo and Nb) and ceramics (SiC and Ti_3SiC_2). All specimens were immersed in molten LBE at 700℃ in a corrosion test pot for 1 000 hours. The tungsten and molybdenum showed high corrosion resistance with no penetration of LBE into their matrices. Penetration of LBE into the matrix of the niobium was observed. The ceramic materials of SiC and Ti_3SiC_2 showed high corrosion resistance with no penetration of LBE into their matrices. The SiC/SiC composite showed LBE penetrated into the matrix due to high porosity of the material.