Sintering Ceramics at Room Temperature using Phase-Changing Additives

在陶瓷部件的整个生命周期中，高达90%的能源都是在制造过程中消耗的。尽管陶瓷材料适合用于包括固态电池和其他设备在内的广泛应用，但使用的非常高的温度是迄今为止阻碍陶瓷材料广泛使用的最大障碍。在这个项目中，我们将尝试消除加热致密化陶瓷材料的需要。我们将从由高纯陶瓷粉末压制而成的颗粒开始，我们将在其中添加非常谨慎地控制数量的“相变添加剂”物质，这些物质在相对较低的温度下转化为金属。这将为我们提供一种通过将材料连接到电源来输入能量的方法，电源将优先加热放置这些物质的颗粒的表面。我们假设这将导致该地区局部的强烈加热，使烧结能够进行，而不需要提高整个样品的温度。这种转变模式的想法将从根本上降低陶瓷行业的能源消耗，并使陶瓷与其他材料的共加工成为可能，这些材料通常会在传统陶瓷加工方法的高温下降解。如果这项工作取得成功，将为包括固态电池和用于成像和通信的陶瓷基金属化超材料在内的重要技术应用提供更好的制造路线。在这个项目中，我们提出了几种方法来研究我们的假设是否正确，以及我们提出的影响是否可以得到足够的控制，以导致广泛的致密化。我们还将通过替换具有不同离子、电性和热导率的材料来研究这些效应的普适性。该项目还将涉及广泛的工作，以表征使用广泛的成像、X射线光谱学和整体性质测量方法生产的样品。

Up to 90% of the energy used over the lifetime of a ceramic component is consumed during manufacturing. The very high temperatures used are by far the biggest barrier to the wider use of ceramic materials, despite their suitability for use in a wide range of applications including solid-state batteries and other devices. In this project we will attempt to eliminate the need for heating to densify ceramic materials. We will start with pellets pressed from highly pure ceramic powders to which we will add very carefully controlled amounts of "phase-changing additive" substances which convert to metals at relatively low temperatures. This will provide us with a way to input energy by connecting the material to a power supply which will preferentially heat the surfaces of the particles where these substances are placed. We hypothesize that this will lead to intense heating in this region locally, enabling sintering to occur without needing to raise the temperature of the entire sample. This paradigm-shifting idea would radically reduce energy consumption in the ceramics industry and enable co-processing of ceramics with other materials which would usually degrade at the high temperatures of conventional ceramic processing methods. This work, if successful, will enable better manufacturing routes for important technological applications including solid-state batteries and ceramic-based metalized metamaterials for use in imaging and communication. In this project we propose several methods to investigate whether our hypothesis is correct and whether the effects we propose can be sufficiently controlled to lead to extensive densification. We will also investigate how universal the effects are by substituting materials with different ionic, electrical, and thermal conductivities. The project will also involve extensive work to characterise the samples produced using a wide range of imaging, X-ray spectroscopy, and bulk property measurement methods.