Gilshtein Evgeniia, Pfeiffer Stefan, Rossell Marta D, Sastre Jordi, Gorjan Lovro, Erni Rolf, Tiwari Ayodhya N, Graule Thomas, Romanyuk Yaroslav E
Laboratory for Thin Films and Photovoltaics, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland.
Laboratory for High Performance Ceramics, Empa - Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600, Dübendorf, Switzerland.
Sci Rep. 2021 Feb 11;11(1):3536. doi: 10.1038/s41598-021-82896-9.
The sintering of alumina (AlO) traditionally occurs at high temperatures (up to ca. 1700 °C) and in significantly long times (up to several hours), which are required for the consolidation of the material by diffusion processes. Here we investigate the photonic sintering of alumina particles using millisecond flash lamp irradiation with extreme heating rates up to 10 K/min. The limitation of the low visible light absorption of alumina is resolved by adding colored α-FeO nanoparticles, which initiated the grain growth during sintering. After the millisecond-long light pulses from a xenon flash lamp, a bimodal mixture of α-AlO precursor particles was sintered and iron segregation at the grain boundaries was observed. The proposed photonic sintering approach based on doping with colored centers may be extended to other refractory ceramics with low absorption in the visible light range once appropriate high-absorbing dopants are identified.
传统上，氧化铝（AlO）的烧结发生在高温（高达约1700°C）且时间极长（长达数小时）的条件下，这是通过扩散过程使材料固结所必需的。在此，我们研究了使用毫秒级闪光灯照射对氧化铝颗粒进行光子烧结，其加热速率高达10 K/min。通过添加有色α-FeO纳米颗粒解决了氧化铝可见光吸收低的问题，这些纳米颗粒在烧结过程中引发了晶粒生长。在来自氙闪光灯的毫秒级光脉冲之后，烧结了α-AlO前驱体颗粒的双峰混合物，并观察到晶界处的铁偏析。一旦确定了合适的高吸收性掺杂剂，基于掺杂色心提出的光子烧结方法可能会扩展到其他在可见光范围内吸收率低的耐火陶瓷。
