Transient liquid phase sintering of LCCC(La_0.8Ca _0.2Cr_0.9Co_0.1O_3-σ) with the addition of CaCrO₄

In this study, in order to improve densification of La_0.8Ca _0.2Cr_0.9Co0.1O_3-σ (LCCC), which is known for one of the most proper candidate interconnector materials in the solid oxide fuel cells, CaCrO₄ was prepared via solid oxide synthesis route and added to the LCCC with different amount and particle sizes. As the amount of the CaCrO₄ increased, porosity of the sintered samples increased, and the pore size was proportional to the particle size of the CaCrO₄. This supports the fact that the CaCrO₄ phase forms liquid during sintering and permeate into the matrix leaving behind large pores. Then the liquid reacts with the matrix through the solid solution. However, when the samples were sintered with a slow ramp up rates, the porosity decreased. This is thought to be caused by the progressive solid solution of CaCrO₄ before the temperature reach to the melting temperature and forms a fluent amount of liquids. The sintering behavior of the LCCC with the addition of CaCrO₄ was analyzed through the transient liquid phase sintering on the basis of the microstructure observation and phase identification by x-ray diffraction.