TY - JOUR
T1 - Mechanical activation of the decomposition and sintering of kyanite
AU - Aguilar-Santillán, Joaquín
AU - Cuenca-Alvarez, Ricardo
AU - Balmori-Ramírez, Heberto
AU - Bradt, Richard C.
PY - 2002/10
Y1 - 2002/10
N2 - The influence of attrition milling on the thermal decomposition of kyanite (Al 2O 3·SiO 2) to mullite (3Al 2O 3·2SiO 2) and SiO 2, and its subsequent sintering, was studied. A commercial kyanite was attrition-milled for times up to 12 h. Dilatometry confirmed that as-received unmilled kyanite decomposes between 1300° and 1435°C. The decomposition reaction is slow initially and accelerates during the later stages until about one-half of the decomposition occurs in the last 35°C. For the attrition-milled kyanite, the onset decomposition temperature decreases, the transformation temperature interval is reduced, and both the decomposition reaction and subsequent sintering are accelerated. A dense microstructure of fine equiaxed mullite grains in the 1 μm size range, evenly dispersed in a glassy matrix, is obtained by sintering the attrition-milled kyanites. These results are explained in terms of the energy accumulated during attrition milling, a reduction of the milled kyanite particle size, and the presence of a liquid phase during sintering.
AB - The influence of attrition milling on the thermal decomposition of kyanite (Al 2O 3·SiO 2) to mullite (3Al 2O 3·2SiO 2) and SiO 2, and its subsequent sintering, was studied. A commercial kyanite was attrition-milled for times up to 12 h. Dilatometry confirmed that as-received unmilled kyanite decomposes between 1300° and 1435°C. The decomposition reaction is slow initially and accelerates during the later stages until about one-half of the decomposition occurs in the last 35°C. For the attrition-milled kyanite, the onset decomposition temperature decreases, the transformation temperature interval is reduced, and both the decomposition reaction and subsequent sintering are accelerated. A dense microstructure of fine equiaxed mullite grains in the 1 μm size range, evenly dispersed in a glassy matrix, is obtained by sintering the attrition-milled kyanites. These results are explained in terms of the energy accumulated during attrition milling, a reduction of the milled kyanite particle size, and the presence of a liquid phase during sintering.
UR - http://www.scopus.com/inward/record.url?scp=0036803757&partnerID=8YFLogxK
U2 - 10.1111/j.1151-2916.2002.tb00475.x
DO - 10.1111/j.1151-2916.2002.tb00475.x
M3 - Artículo
SN - 0002-7820
VL - 85
SP - 2425
EP - 2431
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
IS - 10
ER -