A comparative study of the γ/γ′ eutectic evolution during the solidification of Ni-base superalloys

S. M. Seo, J. H. Lee, Y. S. Yoo, C. Y. Jo, Hirofumi Miyahara, K. Ogi

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

The evolution of γ/γ′ eutectic during the solidification of Ni-base superalloys CMSX-10 and CMSX-4 was investigated over a wide range of cooling rates. The microsegregation behavior during solidification was also quantitatively examined to clarify the influence of elemental segregation on the evolution of γ/γ′ eutectic. In the cooling rate ranges investigated (0.9 to 138.4 K/min (0.9 to 138.4 °C/min)), the γ/γ′ eutectic fraction in CMSX-10 was found to be more than 2 times higher than that in CMSX-4 at a given cooling rate. However, the dependence of the γ/γ′ eutectic fraction on the cooling rate in both alloys showed a similar tendency; i.e., the γ/γ′ eutectic fraction increased with increasing the cooling rate and then exhibited a maximum plateau at and above the certain critical cooling rate in both alloys. This critical cooling rate was found to be dependent on the alloy composition and was estimated to be about 12 K/min (12 °C/min) and 25 K/min (25 °C/min) for CMSX-10 and CMSX-4, respectively. The calculated solid compositions based on the modified Scheil model revealed that even a small compositional difference of total γ forming elements in the initial composition of the alloy can play a significant role in the as-cast eutectic fraction during the solidification of Ni-base superalloys. The evolution of the γ/γ′ eutectic fraction with respect to the cooling rate could be rationalized by taking into account the effects of back-diffusion in solid and dendrite arm coarsening on decreasing the extent of microsegregation.

Original languageEnglish
Pages (from-to)3150-3159
Number of pages10
JournalMetallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
Volume42
Issue number10
DOIs
Publication statusPublished - Oct 1 2011

Fingerprint

heat resistant alloys
Superalloys
eutectics
Eutectics
solidification
Solidification
Cooling
cooling
Chemical analysis
Diffusion in solids
Dendrites (metallography)
Coarsening
dendrites
casts
plateaus
tendencies

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanics of Materials
  • Metals and Alloys

Cite this

A comparative study of the γ/γ′ eutectic evolution during the solidification of Ni-base superalloys. / Seo, S. M.; Lee, J. H.; Yoo, Y. S.; Jo, C. Y.; Miyahara, Hirofumi; Ogi, K.

In: Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, Vol. 42, No. 10, 01.10.2011, p. 3150-3159.

Research output: Contribution to journalArticle

@article{a388779e6ec74ea18c4ef1c88dc79e23,
title = "A comparative study of the γ/γ′ eutectic evolution during the solidification of Ni-base superalloys",
abstract = "The evolution of γ/γ′ eutectic during the solidification of Ni-base superalloys CMSX-10 and CMSX-4 was investigated over a wide range of cooling rates. The microsegregation behavior during solidification was also quantitatively examined to clarify the influence of elemental segregation on the evolution of γ/γ′ eutectic. In the cooling rate ranges investigated (0.9 to 138.4 K/min (0.9 to 138.4 °C/min)), the γ/γ′ eutectic fraction in CMSX-10 was found to be more than 2 times higher than that in CMSX-4 at a given cooling rate. However, the dependence of the γ/γ′ eutectic fraction on the cooling rate in both alloys showed a similar tendency; i.e., the γ/γ′ eutectic fraction increased with increasing the cooling rate and then exhibited a maximum plateau at and above the certain critical cooling rate in both alloys. This critical cooling rate was found to be dependent on the alloy composition and was estimated to be about 12 K/min (12 °C/min) and 25 K/min (25 °C/min) for CMSX-10 and CMSX-4, respectively. The calculated solid compositions based on the modified Scheil model revealed that even a small compositional difference of total γ forming elements in the initial composition of the alloy can play a significant role in the as-cast eutectic fraction during the solidification of Ni-base superalloys. The evolution of the γ/γ′ eutectic fraction with respect to the cooling rate could be rationalized by taking into account the effects of back-diffusion in solid and dendrite arm coarsening on decreasing the extent of microsegregation.",
author = "Seo, {S. M.} and Lee, {J. H.} and Yoo, {Y. S.} and Jo, {C. Y.} and Hirofumi Miyahara and K. Ogi",
year = "2011",
month = "10",
day = "1",
doi = "10.1007/s11661-011-0738-4",
language = "English",
volume = "42",
pages = "3150--3159",
journal = "Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science",
issn = "1073-5623",
publisher = "Springer Boston",
number = "10",

}

TY - JOUR

T1 - A comparative study of the γ/γ′ eutectic evolution during the solidification of Ni-base superalloys

AU - Seo, S. M.

AU - Lee, J. H.

AU - Yoo, Y. S.

AU - Jo, C. Y.

AU - Miyahara, Hirofumi

AU - Ogi, K.

PY - 2011/10/1

Y1 - 2011/10/1

N2 - The evolution of γ/γ′ eutectic during the solidification of Ni-base superalloys CMSX-10 and CMSX-4 was investigated over a wide range of cooling rates. The microsegregation behavior during solidification was also quantitatively examined to clarify the influence of elemental segregation on the evolution of γ/γ′ eutectic. In the cooling rate ranges investigated (0.9 to 138.4 K/min (0.9 to 138.4 °C/min)), the γ/γ′ eutectic fraction in CMSX-10 was found to be more than 2 times higher than that in CMSX-4 at a given cooling rate. However, the dependence of the γ/γ′ eutectic fraction on the cooling rate in both alloys showed a similar tendency; i.e., the γ/γ′ eutectic fraction increased with increasing the cooling rate and then exhibited a maximum plateau at and above the certain critical cooling rate in both alloys. This critical cooling rate was found to be dependent on the alloy composition and was estimated to be about 12 K/min (12 °C/min) and 25 K/min (25 °C/min) for CMSX-10 and CMSX-4, respectively. The calculated solid compositions based on the modified Scheil model revealed that even a small compositional difference of total γ forming elements in the initial composition of the alloy can play a significant role in the as-cast eutectic fraction during the solidification of Ni-base superalloys. The evolution of the γ/γ′ eutectic fraction with respect to the cooling rate could be rationalized by taking into account the effects of back-diffusion in solid and dendrite arm coarsening on decreasing the extent of microsegregation.

AB - The evolution of γ/γ′ eutectic during the solidification of Ni-base superalloys CMSX-10 and CMSX-4 was investigated over a wide range of cooling rates. The microsegregation behavior during solidification was also quantitatively examined to clarify the influence of elemental segregation on the evolution of γ/γ′ eutectic. In the cooling rate ranges investigated (0.9 to 138.4 K/min (0.9 to 138.4 °C/min)), the γ/γ′ eutectic fraction in CMSX-10 was found to be more than 2 times higher than that in CMSX-4 at a given cooling rate. However, the dependence of the γ/γ′ eutectic fraction on the cooling rate in both alloys showed a similar tendency; i.e., the γ/γ′ eutectic fraction increased with increasing the cooling rate and then exhibited a maximum plateau at and above the certain critical cooling rate in both alloys. This critical cooling rate was found to be dependent on the alloy composition and was estimated to be about 12 K/min (12 °C/min) and 25 K/min (25 °C/min) for CMSX-10 and CMSX-4, respectively. The calculated solid compositions based on the modified Scheil model revealed that even a small compositional difference of total γ forming elements in the initial composition of the alloy can play a significant role in the as-cast eutectic fraction during the solidification of Ni-base superalloys. The evolution of the γ/γ′ eutectic fraction with respect to the cooling rate could be rationalized by taking into account the effects of back-diffusion in solid and dendrite arm coarsening on decreasing the extent of microsegregation.

UR - http://www.scopus.com/inward/record.url?scp=80053642598&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=80053642598&partnerID=8YFLogxK

U2 - 10.1007/s11661-011-0738-4

DO - 10.1007/s11661-011-0738-4

M3 - Article

VL - 42

SP - 3150

EP - 3159

JO - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

JF - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

SN - 1073-5623

IS - 10

ER -