Li Jing, Huang Jindi
Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou, Jiangxi 341000, China.
School of Metallurgical Engineering, Jiangxi University of Science and Technology, Ganzhou, Jiangxi 341000, China.
ACS Omega. 2022 May 30;7(23):20219-20228. doi: 10.1021/acsomega.2c02121. eCollection 2022 Jun 14.
This work aims to provide useful insights into the thermal debinding kinetics of gelcast ceramic parts, especially for debinding kinetics prediction involving heat preservation. Debinding experiments were conducted in a differential thermogravimetric analyzer at five heating rates (5, 8, 10, 15, and 20 °C/min) in the temperature range of 35-900 °C under an air atmosphere. The conversion (α) and pyrolysis rate (dα/d) data were simulated using a modified independent parallel reaction (IPR) model and a multiple normally distributed activation energy model (M-DAEM). Their validity was assessed and compared by checking the agreement between the experimental results and the prediction capability. The results showed that both the modified IPR model and M-DAEM had high predictability for thermal debinding kinetics under linear heating conditions. The fitting quality parameters (Fit) were less than 1.406 and 1.01%, respectively. The activation energies ( , = 1, 2, 3, 4, and 5) calculated by the M-DAEM ranged from 153.312 to 217.171 kJ/mol. The relationships between of pseudo components 1 to 5 calculated by the modified IPR model were a function of the conversion rate. The values were (α) = 116.750 + 11.153α - 26.772α + 4.362α kJ/mol, (α) = 139.595 - 66.162α + 75.702α - 38.041α kJ/mol, (α) = 190.854 + 135.755α - 214.801α + 116.093α kJ/mol, (α) = 64.068 + 280.086α - 380.270α + 264.724α kJ/mol, and (α) = 188.257 - 77.086α + 74.129α - 48.669α kJ/mol, respectively. However, it is noteworthy that the α and dα/d curves predicted by the modified IPR model with a deviation of less than 8% were better than those predicted by the M-DAEM for the linear thermal debinding process with the holding stage. Accordingly, it is believed that the proposed modified IPR model is suitable for describing the thermal debinding kinetics involving the heat preservation of gelcast green parts.
这项工作旨在深入了解凝胶注模陶瓷部件的热脱脂动力学，特别是对于涉及保温的脱脂动力学预测。在差示热重分析仪中，于空气气氛下，在35 - 900℃的温度范围内，以五种升温速率（5、8、10、15和20℃/分钟）进行脱脂实验。使用改进的独立平行反应（IPR）模型和多重正态分布活化能模型（M - DAEM）对转化率（α）和热解速率（dα/d）数据进行模拟。通过检查实验结果与预测能力之间的一致性来评估和比较它们的有效性。结果表明，改进的IPR模型和M - DAEM在线性加热条件下对热脱脂动力学都具有较高的预测性。拟合质量参数（Fit）分别小于1.406和1.01%。由M - DAEM计算得到的活化能（ ， = 1, 2, 3, 4, 5）范围为153.312至217.171 kJ/mol。由改进的IPR模型计算得到的伪组分1至5的 之间的关系是转化率的函数。 值分别为 (α) = 116.750 + 11.153α - 26.772α + 4.362α kJ/mol， (α) = 139.595 - 66.162α + 75.702α - 38.041α kJ/mol， (α) = 190.854 + 135.755α - 214.8
