激光熔覆大厚度纳米热障陶瓷涂层成形控制及强韧化机理

项目名称： 激光熔覆大厚度纳米热障陶瓷涂层成形控制及强韧化机理

项目编号： No.51205198

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 机械工程学科

项目作者： 王东生

作者单位： 南京航空航天大学

项目金额： 25万元

中文摘要： 制备大厚度热障涂层是现阶段研究的一个热点。本项目拟在激光熔覆过程中用保温箱对试样进行预热和缓冷处理、引入超声振动及对熔池温度闭环控制等系列熔覆层裂纹控制措施基础上，以压片预置式纳米团聚体陶瓷粉末作为熔覆对象，基于激光多层熔覆的方法，在镍基高温合金表面进行激光熔覆大厚度纳米陶瓷热障涂层的制备技术及强韧化机理研究。课题的主要研究内容包括：压片预置式激光多层熔覆纳米陶瓷涂层试验研究及成形控制；基于遗传神经网络的激光熔覆工艺参数多目标优化；对激光多层熔覆进行热力耦合有限元分析，讨论熔覆层裂纹形成机理，并研究熔覆层裂纹控制措施；建立基于Brook理论的激光熔覆过程中纳米陶瓷颗粒生长模型，并分析纳米陶瓷颗粒对熔覆层的强韧化机理；研究所制备厚纳米陶瓷热障涂层的组织及性能。通过该项目，能够拓展热障涂层的应用范围，建立起一种新的制备大厚度热障涂层的加工方法。

中文关键词： 激光熔覆；多层熔覆；大厚度纳米涂层；热障涂层；

英文摘要： Preparation of thick thermal barrier coatings (TBCs) is a hot research topic at this stage. In this project, the thick nanostructured thermal barrier ceramic coating would be fabricated by squash presetting type laser multi-layer cladding with nanostructured agglomerated powders, and preparation control and reinforced mechanism of laser-clad TBCs will be studied. The crack of clad layer would be controlled by preheating and slow cooling rate of sample with incubator, applying the ultrasonic vibration and closed-loop controlling temperature of molten pool during laser cladding process. The main research as follows: experimental research and preparation control of thick nanostructured ceramic coating by squash presetting type laser multi-layer cladding; process parameters optimization based on neural networks and genetic algorithms; thermal-mechanical coupling finite element analysis of laser multi-layer cladding; discussion of the crack forming during laser cladding process; suggestion of cladding layer crack control measure; nanoparticles growth model during laser cladding process based on brook's theory; reinforced mechanism of nanoparticles; microstructure and property of laser-clad thick nanostructured thermal barrier ceramic coating. It can expand the application scope of TBCs and establish a new preparation

英文关键词： Laser cladding；Multi-layer cladding；Thick nanostructured coating；Thermal barrier coating；