Green properties of dry-pressed alumina compacts fabricated using sucrose as binder

The green density and flexural strength of dry pressed alumina compacts fabricated using sucrose binder (0.6-10.8 wt%) was studied as a function of particle size of alumina powder and moisture content. An optimum binder content (7.2 and 8.4 wt% for fine and coarse alumina, respectively) was established in terms of achieving maximum green density and strength in the pressed compact. Maximum achievable green density of dried samples was 63% and 60% for fine and coarse alumina, respectively. The corresponding maximum strength was 12.5 and 7.52 MPa. Observed results have been co-related with the microstructure of green samples. Samples with sucrose content 3.6 wt% and above were strong enough for green machining. The high green strength of samples could be co-related to plasticizing effect of binder solution leading to maximum particle packing and binder ceramic interaction, as was revealed by IR study. Samples with optimum sucrose content exhibited minimum porosity (5% and 18% for fine and coarse alumina respectively) after firing. 2013 Published by Elsevier Ltd and Techna Group S.r.l.