冷喷纳米双结构生物陶瓷金属梯度复合涂层形成机制与性能

冷喷涂颗粒低温结构移植特性对制备结构热敏感材料涂层具有应用价值。本项目用微纳米磷酸四钙、羟基磷灰石及其与钛复合的粉末，围绕调控低韧性颗粒冷喷塑性变形和沉积率两个制约粒子可控沉积的关键问题，进行不同硬度基体单个粒子沉积，研究不同尺度、成分和结构粒子冷喷塑性变形行为及界面结合特征，探讨不同喷涂工艺条件下粒子特性对其沉积临界速度和碰撞速度的影响。基于粒子特性和喷涂工艺条件调控粒子塑性变形及沉积率，研究冷喷复合粒子成分、组织结构移植和双结构梯度涂层形成机制，探讨涂层成分、组织结构及界面结合随粉末成分结构和喷涂工艺的变化，探讨适合制备双结构纳米磷酸四钙/羟基磷灰石/钛梯度复合生物涂层的可控参量。在此基础上，通过模拟体液浸泡等实验，研究涂层成分、组织结构对其生物和力学的性能影响及在模拟体液中的演化，为制备表面高生物活性、内部高生物稳定性和力学性能匹配的纳米双结构生物陶瓷金属梯度复合涂层提供理论依据。

The structure and composition portability of solid particles at a lower temperature made it potential to fabricate structure thermal sensitive materials by cold spray processes. Focused on the adjusting the plastic deformation and deposition efficiency, the single tetracalcium phosphate/hydroxyapatite/titanium composite particles with different composition, ceramic particle size and porosity was deposited on substrate with different hardness, the deformation and interfacial bonding of adhered splats was examined. The effect of the particle features on its impact velocity and deposition critical velocity in different spray conditions was researched. The transition of structure and composition during cold deposition and the formation of the nano dual-structure gradient composite coatings were researched based on controlling the plastic deformation and depositing efficiency through regulating powder features and spray conditions. The evolution of the composition and microstructure and interfacial bonding of the coating with the spray processes and powder features was researched, and the practicable deposition condition was explored. In addition, the effect of microstructure, composition and phase constitution of the coating on its mechanical performance and biological property was studied through in vitro bioactivity experiment in a simulated body fluid and by mechanical property test, repectively. Based on this research it is expected to have some useful theoretical instructions for fabrication the dual structural nano tetracalcium phosphate/hydroxyapatite/titanium gradient composite coatings with compatible bioactivity, stability and mechanical property.