采用烘箱法和马弗炉法测定氧化镁含水率，工作量大、效率低且误差大。热重分析法可以在程序控制温度条件下快速测定氧化镁含水率，研究了各种因素对热重法测定氧化镁含水率的影响。利用TGA-701型热重分析仪在一定的升温速率、温度和气氛条件下，可一次性获得18个试样的氧化镁自由水率和含水率检测结果。多次试验结果表明：该方法简单、快速、准确且重复性好，10个同批次试样测得的氧化镁自由水率和含水率的相对标准偏差分别为0.62%和2.04%。

The oven method and muffle furnace method for determining moisture content of magnesium oxide, have shortcomings of heavy workload, low efficiency and large error. The thermogravimetric analysis method could be applied to rapidly determine the moisture content of magnesium oxide under the condition of program controlled temperature, and the various factors affecting the determination of moisture content of magnesium oxide were studied. Under the condition of certain heating rate, temperature and atmosphere, by using TGA-701 thermogravimetric analyzer, the free water ratio and moisture content of 18 specimens of magnesium oxide could be obtained for one-time. Multiple test results show that this method is simple, rapid and accurate and has good repetitiveness. The relative standard deviation of free water ratio and moisture content of the same batch of 10 specimens of magnesium oxide was 0.62% and 2.04%, respectively.