Table of Contents
Journal of Metallurgy
Volume 2012 (2012), Article ID 308568, 5 pages
Research Article

Unexpected Precipitation of a Re-Rich Phase in Single Crystal Superalloy CMSX-4 during Thermal Exposure

1Superalloy Division, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China
2High Temperature Materials Group, KIMS, 531 Changwondaero, Changwon 641-010, Republic of Korea
3Materials Test and Characterization Group, KIMS, 531 Changwondaero, Changwon 641-010, Republic of Korea

Received 12 September 2011; Accepted 19 October 2011

Academic Editor: Hao Chen

Copyright © 2012 Kuiyu Cheng et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


A Re-rich phase (up to 85.40% wt.Re) was occasionally found in a single crystal superalloy during thermal exposure. Interestingly, this phase is located in front of the dendrite periphery in the interdendritic region, while the Re is segregated in the dendrite core. Formation of this phase was suggested to relate to the unusual accumulation of the Re resulting from the uneven diffusion process of Re. Appearance of this phase may imply the preference of forming Re-Re atomic bond in the superalloys.