Improvement in strength of γ-LiAlO2 matrixes for a molten carbonate fuel cell (MCFC) via addition of rod-shaped γ-LiAlO2 particles has been investigated. The rod-shaped γ-LiAlO2 particles with the aspect ratio of 9-15 were obtained by heat-treating rod-shaped β-LiAlO2 particles at 800 °C for 3 h, synthesized from the reaction mixture of LiOH-γ-Al2O3-NaOH. The γ-form was very stable for more than 700 h in a molten carbonate environment at 650 °C, while the β-form showed both a phase change from β- to γ-LiAlO2 and a morphology change from rod- to bipyramid-shapes. The average pore size and the porosity of the matrix (550 μm thickness) fabricated by tape-casting of the slurry with weight ratio 1.0 of rod-shaped γ-LiAlO2 particles to commercial γ-LiAlO2 powders (2.0 μm dia.) were about 0.12 μm and 54%, respectively, after being heat-treated at 650 °C for 2 h. The strength (197 gf/mm2) of the rod- shaped particle reinforced matrixes was enhanced more than twice as much as that of the non-reinforced γ-LiAlO2 matrixes (91 gf/mm2).
Bibliographical noteFunding Information:
This work was supported by Korea Electric Power Research Institute, 1997, Advanced Technology Project.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering