对Ni-24.19%Nb过共晶合金在定向凝固速率10μm/s和跃迁减速定向凝固下的组织进行了研究,结果表明:凝固速率10μm/s下,合金中出现了初生Ni3Nb相的生长,并在凝固20mm后达到了准稳态,与最高界面生长温度假设的理论分析相一致.在从10μm/s跃迁减速到1μm/s过程中,界面上液相溶质的变化,造成了初生Ni3Nb相的含量先增加后减少,而初生相的消失,凝固组织变为全耦合生长的共晶组织,主要是由于初生相与共晶相相互竞争生长造成的.另外,初生相的消失也不是在同一个平面上均匀进行的,而是从试样的边缘向中心逐渐发展的.
参考文献
| [1] | ELLIOTT R.Eutectic solidification processing-crystalline and glassy alloys[M].London:Butterworths,1983:92. |
| [2] | 胡汉起.金属凝固原理[M].北京:机械工业出版社,2000:247. |
| [3] | KURZ W;FISHER D J.Fundamentals of solidification[M].Switzerland:Trans Tech Publication,1998:93. |
| [4] | 李双明,马伯乐,李晓历,刘林,傅恒志.定向凝固下共晶合金中相的竞争生长[J].中国科学E辑,2005(05):479-489. |
| [5] | TRIVEDI R;MAGNIN P;KURZ W .Theory of eutectic growth under rapid solidificaiton conditions[J].Acta Materialia,1987,35(04):971-980. |
| [6] | TILLER W A.The Science of Crystallization:Macroscopic Phenomena and Defect Generation[M].Cambridge:Cambridge University Press,1991:191. |
| [7] | Mukherjee S;Zhou ZH;Johnson WL;Rhim WK .Thermophysical properties of Ni-Nb and Ni-Nb-Sn bulk metallic glass-forming melts by containerless electrostatic levitation processing[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,2004(1):21-28. |
| [8] | M. LEONHARDT;W. LOSER .SOLIDIFICATION KINETICS AND PHASE FORMATION OF UNDERCOOLED EUTECTIC Ni-Nb MELTS[J].Acta materialia,1999(10):2961-2968. |
| [9] | TRIVEDI R;KURZ W .Solidification microstructures-A conceptual approach[J].Acta Metallurgica Et Materialia,1994,42(01):15-23. |
| [10] | BURDEN M H;HUNT J D .Cellular and dendritic growth[J].Journal of Crystal Growth,1974,22(02):109-116. |
| [11] | MAGNIN P;TRIVEDI R .Eutectic growth:A modification of the Jackson and Hunt theory[J].Acta Metallurgica Et Materialia,1991,39(04):453-467. |
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%