Spinodal decomposing glass ceramic with tailored porous, thermal and dielectric properties

在该项目中，一种新型的玻璃陶瓷材料将在湿化学浸出过程后提供纳米级孔隙度。所述材料组合物的组成将使得在进行温度处理时发生独立分解并产生额外的可浸出相。这种材料将通过特定的胶带铸造工艺制造。为此，原始材料成分被限定为浆料并浇铸到规定的薄板厚度。分解相的形状和大小主要取决于退火步骤。通过这种方法可以得到发生相的均匀分布。埃尔兰根正在研究一些适合这一过程的玻璃。烧结后的分解相将被湿化学蚀刻，孔隙度可以调节。根据孔隙率和孔隙大小，将研究覆盖孔隙的合适的金属化薄膜，例如作为加热元件。为此，将对该薄膜的电气性能和长期稳定性进行研究。作为演示，将制造一个皮拉尼压力传感器，显示这些材料的低导热性和适用性，适用于传感器。此外，材料的介电常数将作为多孔介质材料的进一步有趣性质进行研究。

Within the project a novel glass-ceramic material will be developed providing a nanoscale porosity after a wet chemical leaching process. The material composition will be composed so that while a temperature treatment a spinodal decomposition occurs and an additional leachable phase originates. This material will be manufactured by a specific tape casting process. For that, the original material composition is conditioned as slurry and cast to a defined sheet thickness. The shape and size of the decomposed phases depends mainly on the annealing steps. By this procedure a homogeneous distribution of the occurring phase can be achieved. There are some suitable glasses for this process being investigated in Erlangen. After sintering the decomposed phase will be wet chemically etched and the degree of porosity can be adjusted. Depending on the porosity and the pore size a suitable thin film metallization will be investigated covering the pores and being suitable e.g. as heater element. For that, the film will be investigated with respect to its electrical performance and long term stability. As demonstrator, a Pirani pressure sensor will be manufactured, showing the low thermal conductivity and suitability of these materials for the applicability within sensors. Additionally, the permittivity of the material will be investigated as further interesting property of porous dielectric materials.