DYNAMIC MODELING OF MATERIAL AND PROCESS PARAMETER EFFECTS ON SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS OF TITANIUM CARBIDE CERAMICS
DYNAMIC MODELING OF MATERIAL AND PROCESS PARAMETER EFFECTS ON SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS OF TITANIUM CARBIDE CERAMICS
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DOI：
10.1007/bf01116030
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发表时间：
1992-06-15
影响因子：
4.5
通讯作者：
KOTTKE, T
中科院分区：
文献类型：
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作者：
ADVANI, AH;THADHANI, NN;KOTTKE, T
通过自蔓延高温合成 (SHS) 进行碳化钛 (TiC) 陶瓷加工的动态有限差分模型评估表明，材料和工艺参数对 SHS 反应传播动力学有显着影响。对 Ti:C 化学计量变化和初始 (Ti + C) 反应物粉末混合物中预反应 TiC 稀释剂存在的影响的检查表明，非化学计量比和稀释添加往往会降低 SHS 反应速度。另一方面，提高压坯预热温度、降低粉末粒径和提高压坯堆积密度会导致该反应变量显着增加。模型结果得到了有关稀释、化学计量和预热温度对 SHS 速度影响的实验研究，以及有关堆积密度和颗粒尺寸对此参数影响的其他文献数据的支持。模拟还表明，这些初始条件的影响是由于它们对绝热反应温度和过程中产生的传热模式的影响。因此，在 TiC 陶瓷的 SHS 加工过程中，初始材料和工艺条件的关键选择似乎至关重要。
A dynamic, finite-difference model evaluation of titanium carbide (TiC) ceramic processing by self-propagation high-temperature synthesis (SHS) has revealed that material and process parameters have a significant influence on SHS reaction propagation kinetics. Examination of the effects of Ti:C stoichiometry variations and the presence of pre-reacted TiC diluents in the initial (Ti + C) reactant powder mix indicates that off-stoichiometric ratios and dilution additions tend to lower SHS reaction velocities. Increasing compact preheat temperatures, lowering powder particle sizes and raising compact packing densities, on the other hand, cause a significant increase in this reaction variable. Model results are supported by experimental studies on dilution, stoichiometry and preheat temperature effects on SHS velocity, and other literature data on packing density and particle size effects on this parameter. Simulations also suggest that effects of these initial conditions are due to their influence on adiabatic reaction temperatures and heat transfer patterns produced during the process. Critical selection of initial material and process conditions thus appears to be of vital importance during SHS processing of TiC ceramics.