激光熔覆钛基生物陶瓷涂层的制备及其界面研究

Preparation and Interface Research of Bioceramic Coating by Laser Cladoping

摘要:

用高功率CO2激光器在Ti-6Al-4V合金表面制备含有生物活性陶瓷相的梯度生物陶瓷涂层。利用扫描电镜(SEM)、X射线衍射(XRD)和电子探针(EPMA)等对熔覆层和界面的显微组织、相组成及成分进行分析。结果表明：激光熔覆复合涂层中生成了羟基磷灰石和磷酸三钙等生物活性相，凹凸不平的表面出现网络交错的片状结构和微孔(孔径为0.5~2 μm)，有利于新骨沿着表面及内部连通微孔攀附生长。涂层与基体界面处存在涂层成分(Ca, P)与基体成分(Ti, Al, V)的互扩散，涂层与基体通过扩散反应形成牢固的冶金结合。残余应力在界面结合区域出现峰值，陶瓷层和过渡层界面附近为221 MPa，涂层与基体界面附近为108 MPa，从涂层到基体残余应力逐渐减小

Abstract:

Based on a high power CO2 laser, the bioceramic coating included bioactive phases was fabricated on the surface of Ti-6Al-4V alloy. The morphology, 他the phase composition and the elemental distribution of the composite and interface were analyzed by SEM, XRD and EPMA. The results show that the bioceramic coating contains such bioactive phases as hydroxyapatite and tricalcium phosphate during laser cladoping. And the interlaced flake structure and micropores of about 0.5~2 μm in size exist on the surface of accidented gradient bioceramic coating, suitable to grow new bone along with the surface and micropore. A solid metallurgically bond to the titanium alloy substrate with the bioceramic coating is set up by the diffusion between the elements of coating (Ca, P) and substrate (Ti, Al, V). The residual stress gradually decreases from coating to substrate, is 221 MPa at the interface between bioceramic coating and transition layer, and 108 MPa between coating and substrate