Microstructure Ti–Fe Phase Separation Mechanism in the Direct Reduction Process of Titanomagnetite with Coal by Microwave Heating

Abstract

Synopsis: Although microwave heating has been used in the field of metallurgy since the 1980s, there are few reports on using microwave heating to strengthen Ti-Fe phase separation in the reduction process of titanomagnetite. Microstructure Ti-Fe phase separation by microwave heating was found to be beneficial to the reduction process of titanomagnetite through the investigation of formation enthalpy and reduction difficulties. The dielectric properties and energy band structure of Fe 3 O 4 , Fe 2 O 3 , and TiO 2 were determined, the dielectric constant (𝜀 ′ 𝑟 : 20.00) and dielectric loss (𝜀 ′ 𝑟 ′ : 2.82) of Fe 3 O 4 were significantly superior to those of TiO 2 (𝜀 ′ 𝑟 : 3.42, 𝜀 ′ 𝑟 ′ : 0.04), and the physical thermal stress between Fe 3 O 4 and TiO 2 phases in the reduction process was conducive to the microstructure Ti-Fe phase separation process. Besides thermal stress, microstructure Ti-Fe phase separation was mainly due to the ampere traction force generated between local isotropic ring current in adjacent iron atoms. This study revealed the microstructure Ti-Fe phase separation mechanism in the reduction process of titanomagnetite by microwave heating.