Yoshinari M, Ozeki K, Sumii T
Tokyo Dental College.
Bull Tokyo Dent Coll. 1991 Nov;32(4):147-56.
To improvement the brittleness of hydroxyapatite (HAp) coated on titanium alloy (Ti-6Al-4V), a thin ceramic layer was formed by means of the RF ion-plating method. The alloy substrates were coated with HAp at 1, 3 or 5 microns thickness and heat-treated at 500 degrees C for 4 hours. Properties of HAp-coated alloy were evaluated by characterization of the ceramic films both before and after heat-treatment, as well as by bending, electrochemical and dissolution tests. HAp-coated film had a slightly higher Ca/P ratio than the original material and was stoichiometrically Ca10(PO4)6(OH)2 by EPMA analysis. HAp was mainly recognized crystallographically by XRD analysis of the films after heat treatment, though it was hardly recognized on before heat-treatment film. These coated materials had a residual strain ranging from 0.3 to 0.7% without causing cracks in the HAp films with the three-point bend testing. Electrochemically, it was confirmed that the corrosion resistance of the Ti alloy was improved by any coating process. The amounts of Ca released from HAp coated film in 0.9% NaCl solution tended to increase with films that were 3 and 5 microns in thickness, but there were no significant differences in Ca released from film before and after heat treatment.
为了改善涂覆在钛合金（Ti-6Al-4V）上的羟基磷灰石（HAp）的脆性，通过射频离子镀法形成了一层薄陶瓷层。合金基底涂覆有厚度为1、3或5微米的HAp，并在500℃下热处理4小时。通过对热处理前后陶瓷膜的表征以及弯曲、电化学和溶解试验来评估HAp涂覆合金的性能。通过电子探针微区分析（EPMA），HAp涂覆膜的Ca/P比略高于原始材料，化学计量比为Ca10(PO4)6(OH)2。通过对热处理后膜的X射线衍射（XRD）分析，HAp主要在晶体学上被识别，尽管在热处理前的膜上几乎无法识别。通过三点弯曲试验，这些涂覆材料的残余应变范围为0.3%至0.7%，且HAp膜未出现裂纹。在电化学方面，证实了任何涂覆工艺都能提高钛合金的耐腐蚀性。在0.9% NaCl溶液中，HAp涂覆膜释放的Ca量倾向于随着膜厚度为3微米和5微米而增加，但热处理前后膜释放的Ca量没有显著差异。
