Liu Wenchao, Xu Feng, Li Yongcun, Hu Xiaofang, Dong Bo, Xiao Yu
CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei 230026, China.
Department of Mechanics, Taiyuan University of Technology, Taiyuan 030024, China.
Materials (Basel). 2016 Feb 23;9(3):120. doi: 10.3390/ma9030120.
This research aims to deepen the understanding of the interaction mechanisms between microwave and matter in a metal-ceramic system based on synchrotron radiation computed tomography. A special internal "core-shell" microstructure was discovered for the first time and used as an indicator for the interaction mechanisms between microwave and matter. Firstly, it was proved that the microwave magnetic field acted on metal particles by way of inducing an eddy current in the surface of the metal particles, which led to the formation of a "core-shell" microstructure in the metal particles. On this basis, it was proposed that the ceramic particles could change the microwave field and open a way for the microwave, thereby leading to selective heating in the region around the ceramic particles, which was verified by the fact that all the "core-shell" microstructure was located around ceramic particles. Furthermore, it was indicated that the ceramic particles would gather the microwaves, and might lead to local heating in the metal-ceramic contact region. The focusing of the microwave was proved by the quantitative analysis of the evolution rate of the "core-shell" microstructure in a different region. This study will help to reveal the microwave-matter interaction mechanisms during microwave sintering.
本研究旨在基于同步辐射计算机断层扫描技术，深入了解金属陶瓷系统中微波与物质的相互作用机制。首次发现了一种特殊的内部“核壳”微观结构，并将其用作微波与物质相互作用机制的指示。首先，证明了微波磁场通过在金属颗粒表面感应涡电流的方式作用于金属颗粒，这导致了金属颗粒中“核壳”微观结构的形成。在此基础上，提出陶瓷颗粒可以改变微波场并为微波开辟一条路径，从而导致陶瓷颗粒周围区域的选择性加热，这一点通过所有“核壳”微观结构都位于陶瓷颗粒周围这一事实得到了验证。此外，表明陶瓷颗粒会聚集微波，并可能导致金属陶瓷接触区域的局部加热。通过对不同区域“核壳”微观结构演化速率的定量分析，证明了微波的聚焦。本研究将有助于揭示微波烧结过程中的微波-物质相互作用机制。
