| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 7992698 | Journal of Alloys and Compounds | 2018 | 16 Pages |
Abstract
The influence of withdraw rate during directional solidification and elements Re and Ti on the formation of micropores during homogenization in Ni base single crystal superalloy CMSX-4 is investigated by X-ray tomography method. The results show that the number of micropores below 5â¯Î¼m in sample solidified at 10â¯mm/min after homogenization at 1300â¯Â°C/3â¯h is greater than that in the case of 6â¯mm/min. The number of micropores below 10â¯Î¼m in Re free and Ti free alloys is rather smaller than that of normal CMSX-4 alloy, while the number of micropores between 15â¯Î¼m and 25â¯Î¼m in Ti free alloy is relatively greater than that in Re free alloy. The variation of number of micropores is analyzed based on measurement of primary dendrite arm spacing (PDAS) and segregation ratios of alloying elements, the causes are mainly attributed to reverse segregation tendencies of Re and Ti and their remarkable diffusion coefficient difference, the increasing of PDAS also enhances the propensity of micropores formation during homogenization.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
J.L. Liu, J. Meng, J.J. Yu, Y.Z. Zhou, X.F. Sun,