Yang Y C, Chang Edward, Lee S Y
Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan.
J Biomed Mater Res A. 2003 Dec 1;67(3):886-99. doi: 10.1002/jbm.a.10145.
This study evaluated the Young's modulus, residual stress and strain, bonding strength, and microstructure of the plasma-sprayed hydroxyapatite coating (HAC) on Ti6Al4V substrate with and without immersion in Hank's balanced salt solution (HBSS). The purpose was to explore the possible correlation of HAC durability and mechanical properties of the coating. The results show that the residual stress and strain, Young's modulus, and bonding strength of the HAC after immersion in HBSS are substantially decreased. The decayed Young's modulus and mechanical properties of HACs are accounted for by the degraded interlamellar or cohesive bonding in the coating due to the increased porosity after immersion that weakens the bonding strength of coating and substrate system. The biologic implications of the research are discussed in detail. This study contributes to the arguments that the method to alleviate the dissolution of HAC will increase the bonding strength of the coating system after immersion, which together with the controlled residual stress and strain in the coating might promote the long-term stability of the HA-coated implant.
本研究评估了在Ti6Al4V基体上等离子喷涂羟基磷灰石涂层（HAC）在浸入和未浸入汉克斯平衡盐溶液（HBSS）情况下的杨氏模量、残余应力和应变、结合强度以及微观结构。目的是探究HAC耐久性与涂层机械性能之间可能存在的相关性。结果表明，浸入HBSS后，HAC的残余应力和应变、杨氏模量以及结合强度均大幅降低。HAC杨氏模量和机械性能的衰减是由于浸入后涂层孔隙率增加，层间或内聚结合退化，削弱了涂层与基体系统的结合强度。详细讨论了该研究的生物学意义。本研究支持了这样的观点，即减轻HAC溶解的方法将提高浸入后涂层系统的结合强度，涂层中可控的残余应力和应变可能共同促进HA涂层植入物的长期稳定性。
