In order to improve the sinterability of LaCrO
3, which is one of candidate materials for interconnector of Solid Oxide Fuel Cell, the effect of sintering in reducing atmosphere and Ti substitution of Cr on the sinterability was investigated. Judging from the sintering temperature dependence of density, both of sintering in reducing atmosphere and Ti substitution of Cr improved the sinterability of LaCrO
3. Compared with the sample sintered in air, sinterability of the samples sintered in reducing atmosphere was most promoted in a case of small amount of Ti substitution. X-ray photoelectron spectroscopy analysis of the surface of the sample revealed an existence of Cr
6+ ion in LaCrO
3 sintered in air. On the contrary, Cr
6+ ion was not obviously observed in LaCrO
3 sintered in reducing atmosphere as well as LaCr
0.7Ti
0.3O
3 sintered in air and in reducing atmosphere. Therefore, Ti substitution of Cr and sintering in reducing atmosphere have the same effect on suppression of CrO
3 generation, which is harmful for sintering of LaCrO
3. Microstructure observation revealed that grain growth of LaCrO
3 sintered in air was pronounced, while that of LaCrO
3 sintered in reducing atmosphere and LaCr
0.8Ti
0.2O
3 sintered in air was negligible. Activation energy for shrinkage of LaCrO
3 and LaCr
0.95Ti
0.05O
3 sintered in reducing atmosphere was 262 kJ•mol
-1 and 153 kJ•mol
-1, While that of LaCr
0.8Ti
0.2O
3 sintered in air was greater than those of LaCrO
3 and LaCr
0.95Ti
0.05O
3 sintered in reducing atmosphere. The effect of Ti substitution on sintering of LaCrO
3 should be different in rate controlling process from the effect of sintering under reducing atmosphere.
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