柠檬酸根对电沉积羟基磷灰石/氧化锆过渡涂层的影响

摘要

先后分别在含有ZrO2+的电解液和含有Ca2+、PO43-和柠檬酸根的电解液中,用电化学恒电流方法,于钛表面上制得柠檬酸根-羟基磷灰石/氧化锫过渡涂层.采用扫描电镜(SEM)、能谱仪(EDS)、X-射线衍射(XRD)、红外光谱(FTIR)和万能力学测试仪对过渡涂层进行分析,并对电沉积各个阶段的微观生长机理进行了探讨.结果表明柠檬酸根延长了HA晶体的形核孕育期,涂层由疏松的微米级菊花瓣状变化为致密的近纳米级针状(或片状),ZrO2作为过渡涂层,很好的缓解了HA与钛基热膨胀系数不匹配等缺点.拉伸试验表明,过渡涂层的结合强度较HA涂层从7.40 MPa增加到27.11 MPa.%A new method of electrolytic Cit-HA/ZrO2 double layers coating was successfully conducted on Ti implant alloy in ZrO(NO3)2 aqueous solution and subsequently in the mixed solution of trisodium citrate, Ca(NO3)2 and NH4H2PO4. Each period of the growth micro-mechanism was discussed. The SEM, EDS, FTIR, XRD and adhesion strength test indicate that the incubation period of the HA is prolonged significantly,and the HA cryatals take the morphology of nanoscale-rodlike cone rather than the micron-daisy petal,the composite coating becomes more compact. ZrO2 is used to adjust the thermal expansion coefficient titanium between substrate and HA coating. In addition, compared to pure HA coating, the adhesion strength of electrolytic deposited Cit-HA/ ZrO2 on Ti alloy is dramatically improved form 7.40 GPa to 27.11 GPa.