Sintering and densification behavior of Mn-doped CeO2

The effect of Mn doping on sintering and densification behavior of commerci al CeO2 powder has been investigated in this study. The results from both X -ray diffraction (XRD) and thermal gravimetric-differential thermal analysi s methods indicate no binary compounds are formed between CeO2 and MnO2, an d Mn element exists in the state of Mn2 + (i.e. MnO) in the samples sintere d above 1200 degreesC. Dilatometer measurement and scanning electron micros copy observation confirm that small amount of Mn doping reduces sintering t emperature dramatically and promotes grain boundary mobility. About 1% Mn-d oped CeO2 sintered at 1300 degreesC for 2 h reaches almost full densificati on ( > 99.0% of relative density). compared with similar to 96% of relative density for pure CeO2 sintered at 1525 degreesC for 2 h, and both samples have almost the same grain size. (C) 2001 Elsevier Science B.V. All rights reserved.