Oxidation mechanism of micron-sized aluminum particles in Al-CO2 gradually heating system

2017 International Conference on Structural, Mechanical and Materials Engineering

材料科学;力学

Liu, Y.^1 ; Ren, H.^1 ; Jiao, Q.J.^1

State Key Laboratory of Explosive Science and Technology, School of Mechatronical Engi-neering, Beijing Institute of Technology, No.5 Zhongguancun South Street, Haidian District, Bei-jing

100081, China^1

关键词: Aluminum particle;    Amorphous alumina;    Carbon dioxide atmosphere;    Differential scanning calorimetry methods;    Increasing temperatures;    Oxidation mechanisms;    Temperature range;    Volcano eruptions;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/248/1/012002/pdf
DOI  :  10.1088/1757-899X/248/1/012002

来源: IOP

【 摘 要 】

Micron-sized aluminum powders were heated in carbon dioxide atmosphere through differential scanning calorimetry (DSC) method in this work. Aluminum powders were oxidized into four distinct stages from room temperature to 1500°C. Stage I, amorphous alumina shell turns to γ-Al2O3phase from room temperature to 620°C. Stage II, accompany with the aluminum core melting, alumina shell becomes thicker and fragile at the temperature around 667°C which is the melting point of aluminum. Stage III, in the temperature range of 690-1150°C, alumina shell was broken partially because of the inside pressure. Liquid aluminum spurts out through the weak point which becomes cracks on the surface just like volcano eruption and then oxidized by CO2while the temperature increased from 700°C to 900°C. Stage IV, alumina changes to stable α-Al2O3. From what was presented above, a mechanism of micron-sized aluminum particle oxidation in CO2under gradually increasing temperature condition was proposed as "eruption model".