Liquid-Film-Assisted Ceramic-Metal Bonding

工程陶瓷是许多结构、生物和微电子应用的候选材料。直接制造大型、复杂的陶瓷结构是困难的，经常使用涉及到较小部件的组装和连接的方法。当陶瓷部件被结合到金属结构中以利用其独特的特性时，连接也经常是必要的。组装过程中产生的接口和接头的质量会影响设备的性能。与连接陶瓷相关的困难可能会限制或阻止它们的使用。这项拟议的工作将探索一种新的方法，通过基于高熔点金属的箔中间层来连接结构陶瓷。陶瓷与难熔金属的连接通常涉及到需要高温、长时间、巨大的结合压力以及非常仔细地准备要连接的表面的过程。这些特点使得这些组合和这些工艺对大规模生产没有吸引力。拟议工作的智能优点在于探索使用多层中间层，该中间层结合了高熔点金属Nb和非常薄的低熔点金属Ni的涂层，以提供一种可以在较低温度下实施的连接工艺，通过不需要严格的表面准备或高连接压力的液膜辅助瞬时-液体相连接工艺，快速生产坚固、可靠的耐火接头。这种有利于制造的工艺的更广泛的影响包括创造许多新的机会，以更容易和更经济地制造具有新功能的基于陶瓷的或含有陶瓷的设备。这项研究的基础科学方法将有助于将联合方法扩展到其他系统，同时在这一重要领域教育和培训年轻的研究人员。

Engineering ceramics are candidates for many structural, biological, and microelectronics applications. Direct fabrication of large, complex ceramic structures is difficult, and an approach that involves the assembly and joining of smaller components is often used. Joining is also often necessary when ceramic components are incorporated into metal-based structures to exploit their unique properties. The quality of the interfaces and joints produced during assembly impacts device performance. The difficulties associated with joining ceramics can limit or prevent their use. The proposed work will explore a novel approach to joining structural ceramics by means of foil interlayers based on high-melting-point metals. Joining ceramics to refractory metals has generally involved processes that require elevated temperature, long times, significant bonding pressure, and extremely careful preparation of the surfaces to be joined. Such characteristics make these combinations and these processes unattractive for mass production. The intellectual merit of the proposed work is focused on exploring the use of a multilayer interlayer combining a high-melting-point metal, Nb, and very thin coating layers of a lower-melting-point metal, Ni, to provide a joining process that can be implemented at reduced temperatures to rapidly produce robust, reliable refractory joints by means of a liquid-film-assisted, transient-liquid-phase bonding processing that does not require scrupulous surface preparation or high bonding pressures. The broader impact of such a manufacturing-friendly process includes the creation of many new opportunities to more easily and economically fabricate ceramic-based or ceramic-containing devices with new functionality. The basic science approach underlying the study will help facilitate the extension of the joining approach to other systems, while educating and training young researchers in this vital area.