Study of phase transitions of ultradispersed spinel powder during solid-phase sintering at 1450 °C

Abstract

In this study, ultradispersed spinel powder (UDP) under conditions close to traditional solid-phase sintering at 1450 ○C is investigated to determine its phase transitions. Quantitative composition of the UDP spinel was performed using X-ray microanalysis. The UDP spinel’s phase and thermal analysis were conducted using X-ray diffraction and thermogravimetric thermal analysis (TGA)/differential thermal analysis (DTA). The UDP spinel was heated from room temperature to 600○C, to 1000○C, to 1450○C to detect phase transitions. It was found that the spinel UDP consists of spinel, periclase, and layered double hydroxides phases. When the UDP spinel is heated from room temperature to 1450 ○C, layered double hydroxides decompose to Mg-O phase and stoichiometric spinel.