球墨铸铁凝固显微组织的元胞自动机模拟*

张蕾, 赵红蕾, 朱鸣芳

SIMULATION OF SOLIDIFICATION MICROSTRUC-TURE OF SPHEROIDAL GRAPHITE CAST IRON USING A CELLULAR AUTOMATON METHOD

ZHANG Lei, ZHAO Honglei, ZHU Mingfang

表1 本工作计算所采用的物性参数[19]

Table 1 Physical properties used in the simulation[19]

Parameter Value Unit Partition coefficient kg? 0.49 Liquidus slope of graphite mL,Gr 470 K·%-1 Solidus slope of graphite ms,Gr 284.8 K·%-1 Liquidus slope of austenite mL,g? -90 K·%-1 Eutectic temperature Teut 1153.7+4.865×%Si ℃ Eutectic composition Ceut 4.28 % Gibbs-Thomson coefficient of graphite ГGr 1.9×10-7 m·K Gibbs-Thomson coefficient of austenite Гg 3.7×10-7 m·K Specific heat of liquid cp 880 J·kg-1·K-1 Volume latent heat of austenite LV,g 1.82×109 J·m-3 Volume latent heat of graphite LV,Gr 3.60×109 J·m-3 1.5×10-10 (T>(Teut-200) ℃) Diffusion coefficient in austenite Dg 1.5×10-10exp(-142100/8.314T) m2·s-1 (T≤(Teut-200) ℃) Diffusion coefficient in liquid DL 5.0×10-9 m2·s-1 Degree of the surface energy anisotropy dt 0.6 Degree of the kinetic anisotropy dk 0.6 Density of graphite rGr 2100 kg·m-3 Density of iron rFe 7930 kg·m-3