( 1. 廈門大學(xué) 材料科學(xué)與工程系，廈門 361005;
2. 日本東北大學(xué) 材料科學(xué)系， 日本仙臺 980-8579)
摘 要: 基于Cu-Ni-Sn三元系的相平衡和熱力學(xué)的實驗信息， 采用亞正規(guī)溶體模型描述液相和fcc相的Gibbs自由能， 為了預(yù)測該體系中bcc相的A2-B2有序-無序轉(zhuǎn)變， bcc相的Gibbs自由能采用雙亞點陣模型進行描述。 利用CALPHAD(相圖計算)方法評估了Cu-Ni-Sn三元系各相的熱力學(xué)參數(shù)， 計算的富Cu側(cè)相圖和熱力學(xué)性質(zhì)與實驗數(shù)據(jù)比較一致。 并對該三元系中bcc相的A2-B2有序-無序轉(zhuǎn)變及fcc相的溶解度間隙進行了計算。 這些計算結(jié)果對利用析出強化以及Spinodal分解開發(fā)高強度和高導(dǎo)電性的新型Cu基合金的組織設(shè)計具有一定的指導(dǎo)意義。
關(guān)鍵字: Cu-Ni-Sn三元系； 相圖； 相圖計算方法； 熱力學(xué)計算
I. Ohnuma2, R. Kainuma2, K. Ishida2
（ 1. Department of Materials Science and Engineering, Xiamen University,
Xiamen 361005, China;
2. Department of Materials Science, Graduate School of Engineering,
Tohoku University, Aoba-yama 02, Sendai 980-8579, Japan）
Abstract: On basis of the phase equilibria and thermodynamic properties of the Cu-Ni-Sn ternary system by experiment, the thermodynamic assessment of the Cu-Ni-Sn ternary system was carried out by the CALPHAD (calculation of phase diagrams) method. The Gibbs free energies of liquid and fcc phases were described by the subregular solution model, and Gibbs free energies of the bcc phase were described by the sublattice model in order to predict the order-disorder phase transition in the bcc phase. A set of parameters describing the Gibbs energies of different phases in this system were optimized by experimental data. The calculated results agree well the experimental data. The A2/B2 ordering temperature and miscibility gap of the fcc phase can be predicted. These calculated results provide an effective guide for microstructure design of the new type Cu base practical materials with high strength and high electric conductivity.
Key words: Cu-Ni-Sn ternary system; phase diagram; CALPHAD method; thermodynamic calculation
