纳米复合硬质涂层中非晶组织的控制与致韧机理研究

项目名称： 纳米复合硬质涂层中非晶组织的控制与致韧机理研究

项目编号： No.51201033

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 金属材料学科

项目作者： 张旭海

作者单位： 东南大学

项目金额： 25万元

中文摘要： 高硬度与韧性难以兼得是高硬度、超高硬度涂层长期面临的瓶颈问题。现有研究表明构造纳米晶/非晶复合硬质涂层可成为解决这一问题的有效途径。但此类涂层致韧机理尚不明确，且相关研究大多集中在纳米晶、纳米晶与非晶晶界中，导致涂层中非晶的选择、设计和控制具有一定的盲目性。基于此，本项目从非晶的新角度出发，以复合不同类型、不同尺寸非晶的TiN系硬质涂层为研究对象，以涂层中非晶的形变机制为切入点，以原位微区观察和实时原位微区观察为主要研究手段，明晰非晶种类和尺寸等因素对涂层韧性的影响，结合分子动力学计算，探索非晶在纳米复合硬质涂层中的致韧机理，并在此基础上提出纳米复合硬质涂层性能（硬度和韧性）优化综合策略。这不仅对推进我国高硬高韧涂层的发展具有重大现实意义，且将促进材料学和理论数值模拟的相互交叉渗透发展，丰富相关研究邻域的基础理论，具有重大学术价值。

中文关键词： 纳米复合；非晶；韧性；硬度；形变

英文摘要： Hard and super hard coatings require a trade-off between high hardness and high toughness. However the recent research shows that nanocomposite coatings with microstructures comprising of nanocrystalline grains in an amorphous matrix can produce unique combination of both high hardness and toughness. The toughening mechanism based on the nanocomposite structure is still not clear and most of the research focus on the plastic deformation in nanocrystals or the phase boundary between nanocrystals and amorphous phase, leaving the amorphous matrix neglected. As a result, the amorphous matrix designing and controlling remains as a hit-and-miss job. Therefore this research will investigate the toughening mechanism of nanocomposite coatings based on the characteristics of amorphous matrix. A serials of TiN coatings containing amorphous carbon，silicon nitride or boron nitride will be used to examine the deformation mode of the amorphous matrix by in situ observation. A molecular simulated will also be adopted to probe the deformation mechanism of the amorphous matrix. Finally the relationship among the structure and size of the amorphous matrix, the deformation mode of the amorphous matrix and the toughness of the hard coatings will be clarified and a performance optimization will be proposed. Thus this research will no

英文关键词： nanocomposite；amorphous；toughness；hardness；deformation