DONG-MEI LI
School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
XIN-BO XIONG
Corresponding author.
Shen Zhen Key Laboratory of Special Functional Materials, Department of Materials Science and Engineering, Shen Zhen University, Shen Zhen 518060, China
XIE-RONG ZENG
Shen Zhen Key Laboratory of Special Functional Materials, Department of Materials Science and Engineering, Shen Zhen University, Shen Zhen 518060, China
CHUN-LI ZOU
Shen Zhen Key Laboratory of Special Functional Materials, Department of Materials Science and Engineering, Shen Zhen University, Shen Zhen 518060, China
JI-ZHAO ZOU
Shen Zhen Key Laboratory of Special Functional Materials, Department of Materials Science and Engineering, Shen Zhen University, Shen Zhen 518060, China

Received 14 April 2009

Carbon/carbon composites with hydroxyapatite coatings are one of the attractive materials in the dental and orthopedic fields. In this study, hydrothermal treatment, in KOH aqueous and ammonia solutions, was used to convert an induction-heating-deposited monetite coating to an adherent HA coating on H₂O₂ treated C/C composites. The structure, morphology and chemical composition of the as-received HA coatings were characterized by XRD, FTIR, SEM and EDS. A scratch test was conducted to measure the adhesion of HA coatings to HT–C/C substrate. The results show that well-crystallized carbonate hydroxyapatite coatings could be achieved under the two reaction mediums. However, the as-obtained HA coatings after KOH hydrothermal treatment have higher crystallinity and Ca/P ratio than those after ammonia hydrothermal treatment, and reveal an average critical load of 29 N which is more than two times as high as that for HA coatings after ammonia hydrothermal treatment.

Carbon/carbon composites; hydroxyapatite; coating; hydrothermal treatment; scratch test