(山東大學(xué) 材料液態(tài)結(jié)構(gòu)及其遺傳性教育部重點(diǎn)實(shí)驗(yàn)室, 濟(jì)南 250061)
摘 要: 將Ti與C同時加入Al熔體可制備出Ti與C摩爾比分別大于、 等于、 小于4的3種含不同物相的AlTiC合金： Al-TiAl3-TiC、 Al-TiC、 Al-Al4C3-TiC。對純鋁的細(xì)化實(shí)驗(yàn)表明： 不含過量Ti的后兩種合金的細(xì)化效果相近， Al4C3在 Al-TiC合金中的大量出現(xiàn)不會進(jìn)一步降低合金的細(xì)化能力; 含TiAl3的第一種合金的細(xì)化效率遠(yuǎn)高于后兩者的； TiC物相在基體中以離散顆粒或聚集團(tuán)形式在Al基體中分布； Al4C3相極脆， 易與空氣中的水蒸汽反應(yīng)而分解。 分析表明Ti與C在Al熔體中反應(yīng)生成TiC是通過兩條途徑同時進(jìn)行的： 熔體中的固體C顆粒與溶解態(tài)的Ti直接反應(yīng)； 固體C顆粒和Al反應(yīng)生成的Al4C3與溶解態(tài)的Ti發(fā)生反應(yīng)。
關(guān)鍵字: AlTiC合金; TiC; 晶粒細(xì)化； Al4C3
C in Al melt
（Key Lab of Liquid Structure and Heredity of Materials, Ministry of Education,
Shandong University, Ji′nan 250061, China）
Abstract:Three kinds of AlTiC alloys with the mole ratio of Ti and C exceeding, equal to or below the stoichiometric value in TiC, i.e. Al-TiAl3-TiC, Al-TiC, and Al-Al4C3-TiC alloys, can be readily produced by a new method involving the simultaneous addition of Ti and C into Al melt. The latter two kinds of alloys have similar refinement efficiencies on pure Al despite of the presence of large amount of Al4C3 phase in Al-Al4C3-TiC, but their efficiencies are much lower than that of the first one due to the absence of excess Ti beyond the combined in TiC in the matrix, suggesting some significant role of excess Ti in the refinement. TiC phase in the alloys exists in the form of discrete particle or small clusters consisting of several discrete particles, which are homogeneously distributed in the matrix. Large agglomerates of TiC particles along grain boundaries were also observed. Al4C3 phase in Al8Ti3.5C is brittle and easy to react with moisture in the air. Analysis shows that formation of TiC is accomplished through the simultaneous reaction of Ti dissolved in the Al melt with either solid carbon particle or Al4C3 phase.
Key words: AlTiC alloy; TiC; grain refinement; Al4C3
