磷酸二氢钾粒度对磷酸钾镁水泥性能影响∗

摘要

KH 2 PO 4作为磷酸钾镁水泥主要原材料,与其性能直接相关.研究了 KH 2 PO 4粒度对磷酸钾镁水泥的流动性、凝结时间、抗压强度、粘接强度、水化浆体温度和孔隙率等方面的影响.结果表明,随着KH 2 PO 4粒径的减小,磷酸钾镁水泥的凝结时间缩短,流动度先增加后减小；材料抗压强度和粘接强度逐渐增大,中位粒径为45μm 时,3 h 抗压强度达32 MPa,1 d 粘接强度达4．3 MPa；KH 2 PO 4的粒度对磷酸钾镁水泥的水化热有较大影响,对于100 mm×100 mm×100 mm 的试块,成型后中心最高温度逐渐升高,最高可达79．5℃；随着 KH 2 PO 4粒径降低,磷酸钾镁水泥的平均孔径降低,孔隙率降低,材料致密程度相应提高.同时,粒径的减小也明显减轻了磷酸钾镁水泥所存在的“泛霜”现象.%As the raw material of potassium-magnesium phosphate cement,KH 2 PO 4 was directly associated with performance of as prepared materials.Effects of KH 2 PO 4 size on setting time,compressive strength,fluidity, adhesive strength,slurry temperature and porosity of the potassium-magnesium phosphate cement are studied in this paper.Results showed that as the KH 2 PO 4 particle size decreases,setting time of potassium-magnesium phosphate cement shortened,fluidity of materials increases and then decreases with minimum particle size in this study ,compressive strength and adhesive strength increases with finer KH 2 PO 4 ,when medium particle size was 45 μm,3 h compressive strength of cement was up to 32 MPa,1 d adhesive strength was 4.3 MPa. Particle sizes of KH 2 PO 4 have significant effects on hydration heat of phosphate potassium magnesium cement. For samples with 100 mm×100 mm×100 mm,central temperature gradually increased,the maximum temper-ature was up to 79.5 ℃.As particle size of KH 2 PO 4 was lessen,mean pore size of phosphate potassium magne-sium cement reduced and lower porosity also can be gotten.The paper also found that finer particle size of KH 2 PO 4 can significantly reduce “efflorescence”phenomenon of the potassium-magnesium phosphate cement.