| 학회 | 한국재료학회 |
| 학술대회 | 2012년 봄 (05/17 ~ 05/18, 무주덕유산리조트) |
| 권호 | 18권 1호 |
| 발표분야 | D. 바이오재료(Biomaterials) |
| 제목 | Formation of hydroxyapatite by hydrothermal treatment of calcite single crystal |
| 초록 | Morphological design of hydroxyapatite (HAp) is one of important prospects on ceramic biomaterials. Hydrothermal treatment is known as a typical processing for fabrication of HAp crystals with unique morphology. On the hydrothermal fabrication of HAp, calcium carbonate was often used as a source of calcium ion. The detailed process of formation of HAp from calcium carbonate under hydrothermal conditions has been not clarified yet. To understand the transformation behavior, we focused on the effects of crystal face of calcite. To obtain two types of crystal faces of calcite, specimens of calcite single crystals which have either {100} or (111) were used. Single crystals of optically clear calcite with {100} or (111) were used as the starting materials. The calcite single crystals with 10×10×1 mm in size were placed in Tefron®-lined autoclaves with a phosphate solution. The sealed autoclave was heated at 160°C. After heating, they were cooled with a fan. The samples were removed from the solution, washed, followed by drying. The cross-sections of the obtained specimens were observed by a scanning electron microscope (SEM). X-ray diffraction (XRD) was used to confirm HAp formation. After the hydrothermal treatment, optically clear specimens became opaque. From the XRD patterns of the samples, HAp formation was confirmed on both surfaces after the hydrothermal treatment. SEM observation on the cross-section of the specimens confirmed that a layer consisting of needle-like and oriented HAp were formed on the surface of the specimen of calcite crystal with {100} face. The HAp formation on the surface of calcite proceeded through dissolution of calcite, and the reaction between calcium and phosphate ions. The crystal growth rate was determined by the dissolution rate of calcium ions from calcite. The (111) plane indicates lower dissolution than {100}. Acknowledgments This work was supported by Grant-in-Aid for Scientific Research (No. 22107007) on the Innovative Areas: “Fusion Materials” (Area no. 2206) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT). |
| 저자 | Ill Yong KIM1, Koichi KIKUTA2, Chikara OHTSUKI1 |
| 소속 | 1Graduate School of Engineering, 2Nagoya Univ. |
| 키워드 | Hydroxyapatite; Morphology; Crystal face; Hydrothermal treatment |
