| Abstract Scope |
In this talk, I will first review a series of our mechanistic studies of flash sintering [Scripta Materialia 146:260 (2018)]. In 2015, we reported that flash sintering generally starts as a thermal runaway [Acta Materialia 94:87 (2015)]. In 2017, we further revealed that ultrahigh heating rates, on the order of ~100 K/s, can enable ultrafast sintering with and without electric fields [Acta Materialia 125:465 (2017)]. Subsequently, ultrafast sintering methods without fields in specimens were demonstrated in collaborative studies [e.g., Science 368:521 (2020), Science Advances 8:eabn8241 (2022), and Nature 623:964 (2023)], enabled by the same underlying mechanism. Nonetheless, electric fields can influence microstructural evolution. For example, our combined experiments and modeling studies showed that applied electric fields can induce grain boundary redox transitions electrochemically to trigger abnormal grain growth [Nature Communications 12:2374 (2021)] or create continuously graded microstructures [Materials Today 73:66 (2024)]. Several on-going projects will also be discussed. |