Properties of Magnesium Oxychloride Cement Prepared Based on Tibet Hydromagnesite  

作　　者：ZHOU Zhifu AN Lingyun CHANG Chenggong DONG Jinmei WANG Ziyi FENG Wenjie 周治富;安凌云;常成功

机构地区：[1]Qinghai Provincial Key Laboratory of Nanomaterials and Technology,Faculty of Chemistry and Materials Science,Qinghai Minzu University,Xining 810007,China [2]Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources,Qinghai Institute of Salt Lake,Chinese Academy of Sciences,Xining 810008,China [3]Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province,Xining 810008,China [4]Tibet Mag Technology Co.,Ltd.,Golmud 816000,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2025年第2期487-495,共9页武汉理工大学学报(材料科学英文版)

基　　金：Funded by the Xining Key R&D and Transformation Program(No.2024-Y-11);the Qinghai Province“Kunlun Talents-Highend Innovation and Entrepreneurship Talents”Top Talents。

摘　　要：A new type of magnesium oxychloride cement(MOC)was prepared based on calcined MgO powder from hydromagnesite in Tibet,China,with the addition of MgCl_2,a by-product of potassium extraction from the salt lake.The effect of MgO on the microstructure and properties of magnesium oxychloride cement was investigated under different calcination temperatures and time of hydromagnesite,and the hydration process,pore structure and hydration products of the materials were investigated by isothermal calorimeter,MIP,XRD,and SEM,and the mechanical properties of the materials were examined by compressive strength test.The compressive strength test shows that under the optimal conditions(800℃-2 h),the compressive strength of MOC is 75.65 MPa for 7 d and 87.98 MPa for 28 d in the indoor environment.The main exothermic period of MOC is delayed by about 10 h compared with that of 500℃-2 h and extended by about 30 h in the process of MOC preparation,which led to the alleviation of the exothermic concentration phenomenon,and the initial solidification time of the MOC specimens is 5.25 h,and the final solidification time is 11.82 h.The MOC phase maintained in indoor air for 28 d mainly consist of P5 and unreacted MgO,and the P5 in the matrix shows the slat-like shape and fills the gaps in the form of needles and rods,and the total porosity is 18.55%.

关 键 词：magnesium oxychloride cement HYDROMAGNESITE phase-composition MICROSTRUCTURE mechanical properties 

分 类 号：TG1[金属学及工艺—金属学]