复合电沉积纳米金刚石强化镀层的微结构调控、表征和力学性能研究

项目名称： 复合电沉积纳米金刚石强化镀层的微结构调控、表征和力学性能研究

项目编号： No.11272231

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 冯露

作者单位： 天津大学

项目金额： 95万元

中文摘要： 以我国柴油机中活塞环、汽轮机和制冷压缩机中叶片表面复合电沉积工艺处理中亟待解决的关键技术问题为应用背景，研究复合镀层中纳米金刚石颗粒度、含量与复合镀层硬度、弹性模量及最终应力等力学参数的映射规律，探索制备高强度纳米金刚石复合镀层的有效途径。通过复合镀层形貌表征，研究电沉积制备工艺参数对复合镀层微结构的影响规律，在此基础上对镀层微结构进行调控，为建立纳米金刚石表面修饰与复合镀层的力学性能匹配关系打下基础；原位观察拉伸时复合镀层中微观变形过程，结合图像相关技术及固体力学理论，分析复合镀层内颗粒及晶界微观变形特征，揭示纳米金刚石强化复合镀层机制；使用纳米压痕法及精密微拉伸系统测试复合镀层的力学性能，揭示其成分-组织-性能间的关系，为制备和加工技术提供组织设计原则；通过数值模拟镀层的生长过程，研究各种非平衡动力学过程的协同作用机制，预测复合镀层的力学性能，为主动设计具有高强度复合镀层提供依据。

中文关键词： 纳米金刚石复合镀层；制备工艺；外延生长；塑性变形机制；力-电化学-扩散耦合

英文摘要： The surface of piston ring of diesel engine, vane of steam turbine and cold compressor need to be treated by composite electrodeposition. Nano-diamond particles are used as coating materials on metal and metal alloys to enhance their strength which have substantial importance in engineering application. The effect of deposition parameters on coating microstructure is investigated. The interplay between the granularity and contents of nano-diamound particles in the composite coating and the mechanical properties such as Yang's modulus, hardness and limit strength is studied and established to find effective way to fabricate the composite coating with high performance. By characterizing the microstructure of composite coating, the effect of deposition parameters on coating microstructure is investigated. Based on this way, the method to manipulate the coating microstructure is proposed. The surface modification of nano-diamoud particles on improving mechanical properties of coating is stressed. In situ observations are made on the deformation processes of composite coating under tension. A digital image correlation technique together with solid mechanics theory are adopted to analyze the deformation characterization in particles and grain boundaries and understand the underlying reinforce mechanisms. The mechanica

英文关键词： Nanodiamond composite coating；preparation technology；epitaxial growth；plastic deformation mechanism；coupling between mechanics-electrochemistry and di