• 作者： Lee, Wei-Chang; Chung, Shyan-Lung
• 中文摘要： 本文乃探討鈦和碳進行燃燒合成反應時之引燃現象與反應機構。當以石墨(<325 mesh)為碳源時,反應之引燃溫度大約在1,650到1,720.degree.C之間,且與碳鈦之原子組成比無關; 但是若使用較細的石墨顆粒為碳源時,則引燃溫度顯著地降低,(例如使用小於1.mu.m的石墨時,引燃溫度為 1,400.degree.C)。當以碳黑為碳源時,反應之引燃溫度約為1,050到1,500.degree.C之間,且隨碳鈦的原子組成比偏離1的程度之增加而升高。在本研究中,引燃反應被認為受碳和鈦之間的表面反應速率所控制,而此表面反應則視碳和鈦之間接觸面積的大小而定。由燃燒合成的產物破斷面觀察發現,其顯微組織包含二種不同的形態,一種是晶粒被燒結緻密的團狀物; 另一則為多孔性,細小顆粒的聚結狀組織,此二種不同的結構在產物中的相對含量,隨使用的碳源種類和碳鈦之原子組成比而定。基於引燃反應的過程探索與產物組織形態的分析,提出可能的反應機構。
• 英文摘要： The ignition process and the reaction mechanism of the SHS reaction of Ti and C were experimentally studied. When using graphite particles (<325 mesh) as the carbon source, the ignition temperature (I .T.) ranged from 1,650 to 1,720.degree.C. and was independent of the C/Ti ratio. The I.T. could be significantly lowered by using finer graphite particles (e.g. 1,400.degree.C for <1.mu.m particles). When using carbon black as the carbon source, the I.T. ranges from 1,050 to 1,500.degree.C and was dependent on the C/Ti ratio. The ignition was confirmed in this study to be controlled by the rate of the surface reaction between Ti and C. This surface reaction was consequently determined by the contact surface area between Ti and C. The fractured surfaces of the products showed two different types of morphology, i.e. groups of grains similar to sintered bodies and porous, agglomerated fine particles. Relative quantities of the two types of morphology depended on the type of carbon used and the C/Ti ratio. Possible reaction mechanisms were proposed on the basis of the relationships of these morphologies and the observations of the ignition process.
• 中文關鍵字： 燃燒合成; 反應機構; 鈦; 碳; 燒結; 形態; 反應速率
• 英文關鍵字： Combustion Synthesis; Reaction Mechanism; Titanium; Carbon; Sintering; Morphology; Reaction Rate