In:
Journal of Materials Research, Springer Science and Business Media LLC, Vol. 33, No. 22 ( 2018-11-28), p. 3689-3699
Abstract:
The microstructure evolution of the directionally solidified NiAl–Cr(Mo) planar eutectic lamellar structure was studied at 1150 °C and times of up to 400 h. The planar eutectic lamellar structure is obtained at the withdrawal rate range of 2.5–7.5 μm/s. The interlamellar spacing decreases gradually with increasing the withdrawal rate. The lamellar termination (like angular or smooth) commonly exists in the as-DS alloy. After high temperature treatment, the lamellar structure at 2.5 μm/s (interlamellar spacing, 3.7 μm) is almost stable, only a little migration of termination occurs at 400 h. When the withdrawal rate increases to 4.5 μm/s, the coarsening and migration of termination occur at 200 h. The adjacently coarsened terminations assemble when the coarsening processes to a certain degree, thus resulting in the formation of the blocky Cr(Mo) phase. Similarly, the above instable phenomenon occurs at 7.5 μm/s. The relevant instability mechanisms are discussed.
Type of Medium:
Online Resource
ISSN:
0884-2914
,
2044-5326
DOI:
10.1557/jmr.2018.206
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2018
detail.hit.zdb_id:
54876-5
detail.hit.zdb_id:
2015297-8
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