(1. 賀州學院 化學與生物工程學院,賀州 542899;
2. 上海交通大學 輕合金精密成型國家工程研究中心,上海 200240;
3. 上海交通大學 金屬基復合材料國家重點實驗室,上海 200240)
摘 要: 用熱重法測定鎂熔體在HFC-32(二氟甲烷)/CO2氣氛中的氧化動力學曲線,用XPS和XRD表征表面氧化膜中氧化產(chǎn)物的組成,討論鎂熔體在HFC-32/CO2氣氛中的氧化機理。結(jié)果表明:鎂熔體在HFC-32/CO2氣氛中的氧化行為遵循拋物線規(guī)律,氧化膜的組成與HFC-32的濃度和溫度有關;隨著HFC-32濃度的增大,氧化膜中MgO的含量減小,MgF2的含量增大,氧化速率減小;隨著溫度的升高,氧化膜中MgO的含量增大,MgF2的含量減小,氧化速率增大。
關鍵字: 鎂熔體;氧化動力學;氧化機理;CH2F2(HFC-32)
(1. School of Chemical and Biological Engineering, Hezhou University, Hezhou 542899, China;
2. National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University,
)
Abstract:The oxidation kinetic curves of molten magnesium in atmospheres of HFC-32 (methylene fluoride)/CO2 were measured by the weight gain method. The oxidation products contents of oxidation surface film were characterized by XPS and XRD. The oxidation mechanism of the magnesium in the mixed gas of HFC-32/CO2 was discussed. The results show that the oxidation behavior follows parabolic law and the film compositions change with the concentration of HFC-32 and the oxidation temperature. With the increase of the HFC-32 concentration in the mixed gas, the content of MgO in the oxide film decreases, the content of MgF2 increases, and the oxidation rate decreases. As the temperature increases, the content of MgO in the oxide film increases, the content of MgF2 decreases, and the oxidation rate increases.
Key words: molten magnesium; oxidation kinetics; oxidation mechanism; CH2F2(HFC-32)


