Premium
Decomposition Mechanisms in Aluminum Oxide–Apatite Systems
Author(s) -
Adolfsson Erik,
Nygren Mats,
Hermansson Leif
Publication year - 1999
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1999.tb02176.x
Subject(s) - apatite , thermal decomposition , oxide , fluorapatite , decomposition , thermogravimetric analysis , thermal stability , materials science , aluminum oxide , chemical engineering , aluminium , phase (matter) , mineralogy , inorganic chemistry , chemistry , metallurgy , organic chemistry , engineering
Aluminum oxide was mixed with solid solutions of hydroxyapatite and fluorapatite, prepared by solid‐state reactions, for a study of the relation between composites of apatite and of their phase stability in the presence of aluminum oxide. The amount of water released from the apatite was quantified from thermogravimetric measurements, and the fraction of vacancies present at the onset temperature of its decomposition in the presence of aluminum oxide was estimated. The results show that the decomposition takes place when a certain fraction of vacancies has been formed. By incorporation of F − in the structure, the fraction of vacancies was reduced and the thermal stability of apatite was improved. Based on these findings, a modified mechanism describing the thermal decomposition of hydroxyapatite in the aluminum oxide–hydroxyapatite system is formulated.