Transparent alumina fabricated by SPS sintering with AlF 3 doping

Transparent alumina was fabricated by spark plasma sintering with AlF3 doping at a high heating rate of 100 degrees C min(-1) and a moderate loading pressure of 73 MPa. The sintered AlF3-doped alumina was dark in color due to light absorption by F- substitution and by the resulting defects induced in the alumina lattice. An AlF3 doping concentration of 0.1% was found best for producing transparent alumina. A possible mechanism was proposed to explain the doping effect under the present sintering condition. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.