The Improvement Effects of NaH_(2)PO_(4) and KH_(2)PO_(4) on the Properties of Magnesium Oxysulfate Cement

作     者：WANG Nan YU Hongfa BI Wanli GUAN Yan GONG Wei ZHANG Na WU Chengyou 王南;余红发;BI Wanli;GUAN Yan;GONG Wei;ZHANG Na;WU Chengyou

作者机构：Department of Civil EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China School of Materials and MetallurgyLiaoning University of Science and TechnologyAnshan 114051China School of Civil EngineeringQinghai UniversityXinitig 810016China 

出 版 物：《Journal of Wuhan University of Technology(Materials Science)》 (武汉理工大学学报（材料科学英文版）)

年 卷 期：2021年第36卷第1期

页      面：50-57页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：Supported by the Key Research and Development and Transformation Plan of Qinghai Province-Special Project for Transforming Scientific and Technological Achievements(No.2019-NN-159) 

主　　题：magnesium oxysulfate cement phosphates compressive strength volume stability microstructure 

摘      要：Sodium dihydrogen phosphate (NaH_(2)PO_(4)) and potassium dihydrogen phosphate (KH_(2)PO_(4)) were selected as additives for magnesium oxysulfate (MOS) *** phase composition and the microstructure of MOS cement were characterized using X-ray diffraction (XRD),thermogravimetric analysis (TG-DSC),Flourier transform infrared spectroscopy (FT-IR),mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM).It is found that both NaH_(2)PO_(4) and KH_(2)PO_(4) lead to an increase in the compressive strength and an improvement in the volume stability of MOS *** XRD,MIP and SEM results show that the addition of NaH_(2)PO_(4) or KH_(2)PO_(4) does not change the phase composition of MOS cement but promotes the formation of strength phase of 5Mg(OH)_(2)·MgSO_(4)·7H_(2)O (5·1·7 phase).This phase brings a considerable improvement in the microstructure of MOS cement,which has a positive effect on the properties of MOS cement.