通过对Al-4.5%Cu合金铸锭显微偏析形成的数值模拟,研究了凝固路径对凝固后铸锭不同位置处显微偏析参数的影响.在显微偏析模型中考虑了树枝晶粗化、固相溶质逆扩散、枝晶尖端过冷、随温度变化的溶质扩散系数等影响显微偏析形成的动力学因素.数值方法中采用变网格技术跟踪移动界面,通过迭代求解溶质扩散方程和溶质守恒方程计算显微偏析参数.结果表明,对于Al-Cu合金,固相扩散主要由溶质扩散速率控制,而非局部凝固时间.显微偏析参数不仅取决于局部凝固时间,还要考虑凝固路径的影响.
参考文献
| [1] | 柳百成.铸件凝固过程的宏观及微观模拟仿真研究进展[J].中国工程科学,2000(09):29-37. |
| [2] | Roosz A;Halder E;Exner H E .Numerical calculation of microsegregation in coarsened dendritic microstructures[J].Materials Science and Technology,1986,2(11):1149-1155. |
| [3] | Voller V R;Sundarraj S .Modelling of microsegregation[J].Materials Science and Technology,1993,9(06):474-481. |
| [4] | Sundarraj S;Voller R D .The binary alloy problem in an expanding domain: the microsegregation problem[J].International Journal of Heat and Mass Transfer,1993,36(03):713-723. |
| [5] | Kurz W;Giovanola B;Trivedi R .Theory of microstructural development during rapid solidification[J].Acta Materialia,1986,34(05):823-830. |
| [6] | 刘永刚,孙瑜,邱宗文,孙国雄.显微偏析数值模拟的微观模型和数值方法[J].中国有色金属学报,2004(03):335-339. |
| [7] | 刘永刚,孙瑜,孙国雄.微观结点数目对显微偏析数值模拟的影响[J].中国工程科学,2004(02):77-81. |
| [8] | 刘永刚,陈晋,孙国雄,潘冶.相图计算耦合显微偏析数值模拟的宏/微观数值方法[J].铸造,2003(02):123-125. |
| [9] | Yan X Y;Chen S;Xie F Y et al.Computational and experimental investigation of microsegregation in an Al-rich Al-Cu-Mg-Si quaternary[J].Acta Materialia,2002,50(09):2199-2207. |
| [10] | Boettinger W J;Kattner U R;Banerjee D K.Analysis of solidification path and microsegregation in multicomponent alloys[A].Warrendale,PA:TMS,1998:159-170. |
| [11] | Greven K;Fackeldey M;Ludwig A.Macroscopic modeling of the microstructural evolution in casting using thermodynamic formulated phase diagrams[A].Warrendale,PA:TMS,1998:187-194. |
| [12] | Kraft T;Liang H;Chang Y A.An approximate method for coupling microscopic and macroscopic simulations using calculation phase diagrams[A].Warrendale,PA:TMS,1998:203-210. |
| [13] | Yan X Y;Xie F Y;Chu M et al.Microsegregation in Al-4. 5%Cu alloy: experimental investigation and numerical modelling[J].Materials Science and Engineering,2001,A302(02):268-274. |
| [14] | Sasikumar R;Kraft T;Exner H E .Influence of the shape of the cooling curves on microsegregation[J].Scripta Metallurgica et Materialia,1993,28(02):235-240. |
| [15] | Battle T P;Pehlke R D .Mathematical modeling of microsegregation in binary metallic alloys[J].Metallurgical and Materials Transactions,1990,21(04):357-375. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%