Using fly ash as raw material,the variation rule of sintering rate and heating rate and the relationship between shrinkage and sintering activation energy of fly ash were investigated by thermal dilatometer.Bulk density,water absorption,flexural strength and apparent porosity of sintered fly ash samples were examined as a function of temperature.The effect of sintering tem-perature on mineral phase and microstructure was investigated by X-ray diffraction(XRD)and scanning electron microscopy(SEM).Results indicated that the sintering rate was directly proportional to the heating rate,and a higher heating rate was more favorable for sintering.The sintering activation energy decreased and then increased with increasing shrinkage,and its value was minimum when the shrinkage was 4％.In addition,the fly ash sintered at 1200 ℃ showed the best comprehensive performance,i.e.,bulk density of 2.16 g/cm3,water absorption of 0.36％,flexural strength of 56.06 MPa,and porosity of 0.77％.
维普
万方数据