(1. 湖南工業(yè)大學(xué) 無機(jī)非金屬材料工程技術(shù)湖南省重點(diǎn)實(shí)驗(yàn)室，
株洲 412007;
2. 中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室， 長(zhǎng)沙 410083)
摘 要: 采用分段真空燒結(jié)和化學(xué)分析等研究了納米Ti(CN)基金屬陶瓷壓坯在燒結(jié)過程中的收縮行為、化學(xué)成分和性能的演變。 實(shí)驗(yàn)表明： 納米混合料的壓坯在低溫下由于壓制應(yīng)力釋放和劇烈的還原脫氣（氧）反應(yīng)造成壓坯膨脹； 壓坯中出現(xiàn)液相的溫度比微米Ti(CN)粉末壓坯的要低50 ℃。 由于高溫氮的分解， 造成合金在溫度達(dá)到1 400 ℃以后不但不收縮， 反而膨脹； 納米Ti(CN)混合料壓坯中的總碳含量和氧含量在600 ℃后逐步下降； 壓坯中的氧含量在1 100～1 300 ℃時(shí)迅速下降， 壓坯中的氮含量在1 100 ℃以后才開始下降， 在液相出現(xiàn)前形成高峰， 氮含量越高， 氮的損失越大。 納米混合料的壓坯必須經(jīng)過壓力燒結(jié)后才能獲得高致密的合金，其斷裂韌性要比微米金屬陶瓷提高50%。
關(guān)鍵字: 納米Ti(CN)；金屬陶瓷； 燒結(jié)收縮； 化學(xué)成分； 力學(xué)性能
chemical composition of millicron-Ti(CN)
base cermets during sintering
DING Ze-liang1
（1. Engineering Technology Province Key Laboratory of Inorganic and
Nonmetal Materials, Hunan Industry University, Zhuzhou 412007, China;
2. State Key Laboratory of Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract: Using chemical analysis and vacuum sintering in different temperatures, the evolvement of the shrinkage, chemical composition and properties of the nano-Ti(CN) base cermets during sintering process were studied. Because of pressing stress was released and the deoxidizing and outgassing(oxygen) were happened tempestuously, the nano-cermets green compact was expanded at about 600 ℃. The temperature of liquid phase appear is lower about 50 ℃ than that of micro Ti(CN) powders. Because of the decomposition of nitrogen, the nano-Ti(CN) base cermets began to expand after 1 400 ℃. The total carbon and oxygen content in nano-cermets green compact decline gradually with the increase of sintering temperature, the oxygen content decline rapidly between 1 100-1 300 ℃. The nitrogen content in nano-cermets begins to decline, the decline reach floodtide before the liquid phase appear, the higher of nitrogen content in nano-cermets is, the higher the declining amount is. Only by pressure sintering could the dense alloy be gained, the fracture toughness of nano-Ti(CN) base cermets increase by 50% compared with the micron one.
Key words: nano-Ti(CN); cermets; sintering shrinkage; chemical composition; mechanical properties
