Influence of heat treatment on the distribution of Ni 2Nb and microsegregation in cast inconel 718 alloy

Nader El-Bagoury, Toru Matsuba, Kaoru Yamamoto, Hirofumi Miyahara, Keisaku Ogi

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

The influences of solution and homogenization heat treatments and grain size on the microstructure and mechanical properties of cast Inconel 718 alloy have been investigated. The microstructure of as cast In? 18 alloy consists of primary γ, eutectic (γ + NbC) and eutectic (γ + Ni 2Nb). Fine and coarse grain structure specimens were achieved by controlling casting temperature. The fine grain specimen has a higher volume fraction of Ni 2Nb, 4.99%, than the coarse grain one, 3.45%. The volume fraction of NbC is 1.0 to 1.3% in both fine and coarse grain specimens, and almost unchanged by solution heat treatment. In case of the fine grain specimen, the as cast volume fraction of Ni 2Nb decreases by solution treatment to 1.26% at the temperature of 1403 K for 0.5 h holding time and completely dissolute after 4h at the same temperature. By increasing temperature to 1440 K, it takes only 2h to vanish Ni 2Nb from the microstructure. The coarse grain structure gives lower tensile strength for both as cast and as solution treated in compare with fine grain ones. The volume fraction of Ni 2Nb phase has a significant influence on the tensile strength and strain values, while it has no effect on the yield stress and hardness measurements. The fracture crack during tensile test is selectively initiated at Ni 2Nb phase and propagated along it in interdendritic zone.

Original languageEnglish
Pages (from-to)2478-2483
Number of pages6
JournalMaterials Transactions
Volume46
Issue number11
DOIs
Publication statusPublished - Nov 1 2005

Fingerprint

Inconel (trademark)
casts
heat treatment
Heat treatment
Volume fraction
Crystal microstructure
Eutectics
Microstructure
Tensile strength
eutectics
tensile strength
microstructure
Temperature
Tensile strain
Yield stress
temperature
stress measurement
Casting
Hardness
tensile tests

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Influence of heat treatment on the distribution of Ni 2Nb and microsegregation in cast inconel 718 alloy. / El-Bagoury, Nader; Matsuba, Toru; Yamamoto, Kaoru; Miyahara, Hirofumi; Ogi, Keisaku.

In: Materials Transactions, Vol. 46, No. 11, 01.11.2005, p. 2478-2483.

Research output: Contribution to journalArticle

El-Bagoury, Nader ; Matsuba, Toru ; Yamamoto, Kaoru ; Miyahara, Hirofumi ; Ogi, Keisaku. / Influence of heat treatment on the distribution of Ni 2Nb and microsegregation in cast inconel 718 alloy. In: Materials Transactions. 2005 ; Vol. 46, No. 11. pp. 2478-2483.
@article{3eef51d9d2484a6197958c90be51a010,
title = "Influence of heat treatment on the distribution of Ni 2Nb and microsegregation in cast inconel 718 alloy",
abstract = "The influences of solution and homogenization heat treatments and grain size on the microstructure and mechanical properties of cast Inconel 718 alloy have been investigated. The microstructure of as cast In? 18 alloy consists of primary γ, eutectic (γ + NbC) and eutectic (γ + Ni 2Nb). Fine and coarse grain structure specimens were achieved by controlling casting temperature. The fine grain specimen has a higher volume fraction of Ni 2Nb, 4.99{\%}, than the coarse grain one, 3.45{\%}. The volume fraction of NbC is 1.0 to 1.3{\%} in both fine and coarse grain specimens, and almost unchanged by solution heat treatment. In case of the fine grain specimen, the as cast volume fraction of Ni 2Nb decreases by solution treatment to 1.26{\%} at the temperature of 1403 K for 0.5 h holding time and completely dissolute after 4h at the same temperature. By increasing temperature to 1440 K, it takes only 2h to vanish Ni 2Nb from the microstructure. The coarse grain structure gives lower tensile strength for both as cast and as solution treated in compare with fine grain ones. The volume fraction of Ni 2Nb phase has a significant influence on the tensile strength and strain values, while it has no effect on the yield stress and hardness measurements. The fracture crack during tensile test is selectively initiated at Ni 2Nb phase and propagated along it in interdendritic zone.",
author = "Nader El-Bagoury and Toru Matsuba and Kaoru Yamamoto and Hirofumi Miyahara and Keisaku Ogi",
year = "2005",
month = "11",
day = "1",
doi = "10.2320/matertrans.46.2478",
language = "English",
volume = "46",
pages = "2478--2483",
journal = "Materials Transactions",
issn = "0916-1821",
publisher = "The Japan Institute of Metals and Materials",
number = "11",

}

TY - JOUR

T1 - Influence of heat treatment on the distribution of Ni 2Nb and microsegregation in cast inconel 718 alloy

AU - El-Bagoury, Nader

AU - Matsuba, Toru

AU - Yamamoto, Kaoru

AU - Miyahara, Hirofumi

AU - Ogi, Keisaku

PY - 2005/11/1

Y1 - 2005/11/1

N2 - The influences of solution and homogenization heat treatments and grain size on the microstructure and mechanical properties of cast Inconel 718 alloy have been investigated. The microstructure of as cast In? 18 alloy consists of primary γ, eutectic (γ + NbC) and eutectic (γ + Ni 2Nb). Fine and coarse grain structure specimens were achieved by controlling casting temperature. The fine grain specimen has a higher volume fraction of Ni 2Nb, 4.99%, than the coarse grain one, 3.45%. The volume fraction of NbC is 1.0 to 1.3% in both fine and coarse grain specimens, and almost unchanged by solution heat treatment. In case of the fine grain specimen, the as cast volume fraction of Ni 2Nb decreases by solution treatment to 1.26% at the temperature of 1403 K for 0.5 h holding time and completely dissolute after 4h at the same temperature. By increasing temperature to 1440 K, it takes only 2h to vanish Ni 2Nb from the microstructure. The coarse grain structure gives lower tensile strength for both as cast and as solution treated in compare with fine grain ones. The volume fraction of Ni 2Nb phase has a significant influence on the tensile strength and strain values, while it has no effect on the yield stress and hardness measurements. The fracture crack during tensile test is selectively initiated at Ni 2Nb phase and propagated along it in interdendritic zone.

AB - The influences of solution and homogenization heat treatments and grain size on the microstructure and mechanical properties of cast Inconel 718 alloy have been investigated. The microstructure of as cast In? 18 alloy consists of primary γ, eutectic (γ + NbC) and eutectic (γ + Ni 2Nb). Fine and coarse grain structure specimens were achieved by controlling casting temperature. The fine grain specimen has a higher volume fraction of Ni 2Nb, 4.99%, than the coarse grain one, 3.45%. The volume fraction of NbC is 1.0 to 1.3% in both fine and coarse grain specimens, and almost unchanged by solution heat treatment. In case of the fine grain specimen, the as cast volume fraction of Ni 2Nb decreases by solution treatment to 1.26% at the temperature of 1403 K for 0.5 h holding time and completely dissolute after 4h at the same temperature. By increasing temperature to 1440 K, it takes only 2h to vanish Ni 2Nb from the microstructure. The coarse grain structure gives lower tensile strength for both as cast and as solution treated in compare with fine grain ones. The volume fraction of Ni 2Nb phase has a significant influence on the tensile strength and strain values, while it has no effect on the yield stress and hardness measurements. The fracture crack during tensile test is selectively initiated at Ni 2Nb phase and propagated along it in interdendritic zone.

UR - http://www.scopus.com/inward/record.url?scp=30844448154&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=30844448154&partnerID=8YFLogxK

U2 - 10.2320/matertrans.46.2478

DO - 10.2320/matertrans.46.2478

M3 - Article

AN - SCOPUS:30844448154

VL - 46

SP - 2478

EP - 2483

JO - Materials Transactions

JF - Materials Transactions

SN - 0916-1821

IS - 11

ER -