Liquid‐Phase‐Assisted Sintering of Calcium‐Doped Lanthanum Chromites

Abstract

Investigations have been made on the low‐temperature sinterability of calcium‐doped lanthanum chromites which are to be used as interconnectors in solid oxide fuel cells (SOFCs). Nominally chromium deficient lanthanum calcium chromites (La 0.7 Ca 0.3 Cr 1 ‐ y O 3 , y = 0.02) were found to be sinterable to 94% theoretical density at 1573 K in air, whereas no densification was observed for samples with y = 0. The two‐step shrinkage process suggests a liquid phase sintering mechanism with calcium oxychromates playing an important role as the liquid phase. After sintering at 1573 K, calcium‐rich substances remained at grain boundaries.