LaCrO
3-dispersed Cr alloy for metallic interconnector in solid oxide fuel cell has been studied as a function of LaCrO
3 content in the range of 5 to 25 vol.%, and the sintering and oxidation properties of these alloys were examined. The Cr alloys were prepared from Cr and LaCrO
3 powders, and were sintered at 1500°C under an Ar atmosphere with 5 vol.% H
2. The LaCrO
3-dispersed Cr alloys showed a relative density above 95%, and their sintering densities did not depend on LaCrO
3 content. The LaCrO
3 particles in the sintered alloys existed in grain boundaries of Cr particles, and the size of the Cr particles increased with decreasing LaCrO
3 content. This means that LaCrO
3 particles prevent grain growth of Cr particle during the sintering process. The isothermal oxidation tests of the Cr alloys were carried out for 2500 hrs at 1000°C in air. The oxidation behavior obeyed a logarithmic law probably due to ion diffusion within oxide scale. All Cr alloys show good oxidation resistance as compared with pure Cr, which is considered for LaCrO
3 to increase a density of oxide scale. In particular, Cr alloys with 10 to 20 wt.% LaCrO
3 are very resistant to oxidation. These results indicate that the LaCrO
3-dispersed Cr alloys satisfy the sintered density and oxidation resistance requirements of interconnection material in solid oxide fuel cell.
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