Open AccessImproved hydration resistance of MgO–2CaO·SiO2–3CaO·SiO2 composite refractory using low-grade minerals
Author(s) -
Xuewu Zhan,
Xiaopeng Wu,
Yiqiang Xing,
Xinghui Cui,
Shijie Wang,
Fei fan Zhao,
Meng Wei,
Chengliang Ma,
Zhong Xiangchong
Publication year - 2020
Publication title -
materials research express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.383
H-Index - 35
ISSN - 2053-1591
DOI - 10.1088/2053-1591/abad52
Subject(s) - materials science , magnesite , calcium silicate , composite number , refractory (planetary science) , mineralogy , silicate , calcination , forsterite , silicon , porosity , chemical engineering , magnesium , metallurgy , composite material , chemistry , engineering , catalysis , biochemistry
Three low-grade mineral raw materials, i.e., natural dolomite, high-silicon magnesite, and forsterite tailings were used to prepare a MgO–2CaO·SiO 2 –3CaO·SiO 2 composite refractory, and its hydration resistance was essentially improved. Free CaO was converted into more stable calcium silicate which protected MgO from hydration, and low melting phases formed by impurities promoted densification. The composite refractory, predominantly composed of MgO, β -2CaO·SiO 2 , and 3CaO·SiO 2 with a bulk density of 3.13 g cm −3 and apparent porosity of 4.6%, was obtained after being calcined at 1600 °C for 3 h. The prepared composite exhibited excellent hydration resistance with a weight increase of only 0.03% at 1600 °C. Microstructural analysis revealed that a dense matrix consisting of intergranular calcium–silicate phases, was dispersed by rounded MgO aggregates.