Preparation and refractory properties of high-magnesium nickel slag-metakaolin based geopolymer
This work prepared a high-magnesium slag(HMNS)-metakaolin(MK)based geopolymer by incorporating MK into HMNS.High temperature resistance property of the high-magnesium nickel slag based geopolymer was studied and microscopic characterization techniques such as X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),and synchronous thermal analysis(TG-DSC)were employed to analyze the changes of hydration products,phase transitions,and microstructure changes of the high-magnesium nickel slag based geopolymer.Results show that the compressive strength of the high-magnesium nickel slag based geopolymer can reach 16.0 MPa at room temperature.After exposure to 1200℃,the compressive strength increased to 38.8 MPa with a thermal expansion coefficient of only 1.05％,demonstrating excellent high-temperature resistance.At room temperature,the primary crystalline products are newberyite and berlinite.The amorphous phase mainly consists of structures such as—Al—O—P—,—Si—O—P—,—Si—O—P—O—Al—,and—P—O—Mg—.After exposure to high temperatures,phase transitions,evaporation of physically bound water,dehydration of chemically bound water,dehydroxylation,shrinkage of the gel phase,and sintering are the main factors influencing the mechanical properties and microstructural changes of high-magnesium nickel slag based geopolymer.
high-magnesium nickel slagmetakaolingeopolymerhigh temperature resistance property
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维普
