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、复杂的陶瓷结构是很困难的，通常采用一种包括组装和连接较小部件的方法。当陶瓷部件被整合到金属基结构中以利用其独特的性能时，连接也是经常必要的。装配过程中产生的接口和接头的质量影响设备的性能。连接陶瓷的困难会限制或阻止它们的使用。本研究将探索一种利用高熔点金属箔夹层连接结构陶瓷的新方法。将陶瓷与难熔金属连接通常涉及的过程需要高温、长时间、巨大的连接压力和非常仔细地准备要连接的表面。这些特点使这些组合和这些工艺对大规模生产没有吸引力。所提出的工作的智力价值集中在探索多层中间层结合高熔点金属Nb和低熔点金属Ni的极薄涂层的使用，以提供一种可以在低温下实施的连接工艺，通过液体膜辅助的瞬态液相键合处理，快速产生坚固可靠的耐火接头，不需要严格的表面处理或高键合压力。这种制造友好工艺的更广泛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陶瓷基或含陶瓷设备。这项研究的基础科学方法将有助于促进将加入方法扩展到其他系统，同时教育和培训这个重要领域的年轻研究人员。

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.