Utilization of magnetite as microwave absorber to prepare microwave- heatable aggregate for deicing in cementitious composite

摘要

Magnetically separated fly ash (MSFA) was acquired from ordinary fly ash by using magnetic separator, producing a magnetite content of more than 30% after magnetic separation. A new idea of preparing microwave-heatable aggregate (MHA) is proposed by using magnetite as microwave absorbor. The MHA was prepared by the calcination of MSFA (55 wt% iron oxide) at 1150 degrees C for 30 min, whereby the main mineral phases are albite, fayalite, and magnetite. The microwave deicing time of mortar specimens was much shorter with MHA and increased as the ambient temperature decreased, while the thickness of the ice had no obvious effect on the microwave deicing time. (C) 2019 Elsevier Ltd. All rights reserved.