The microstructure of heat-treated nickel-­based superalloy 718Plus

Lawrence Whitmore; Mohammad Reza Ahmadi; Laure Guetaz; Harald Leitner; Erwin Povoden-Karadeniz; Martin Stockinger; Ernst Kozeschnik

doi:10.1016/j.msea.2014.05.022

The microstructure of heat-treated nickel-based superalloy 718Plus

Lawrence Whitmore^*, Mohammad Reza Ahmadi, Laure Guetaz, Harald Leitner, Erwin Povoden-Karadeniz, Martin Stockinger, Ernst Kozeschnik

^*Corresponding author for this work

Institute of Materials Science, Joining and Forming (3030)

Research output: Contribution to journal › Article › peer-review

Abstract

The microstructure of thermally aged nickel-based 718Plus superalloy is investigated using transmission electron microscopy (TEM). Solution annealing at 980 °C for 30 min is followed by either the standard quenching to room temperature or quenching directly to 788 °C, before isothermal aging at 788 °C for four hours. Micro-hardness and yield strength are measured to compare the effects of the two variations. The size and phase fraction of γ′ precipitates are measured using dark-field TEM and related to the hardness and yield strength through a theoretical model based on coherency and antiphase boundary effects. A population of very small sub-precipitates is observed and the larger γ′ precipitates are investigated in detail using high resolution scanning TEM to reveal information about the chemical ordering.

Original language	English
Pages (from-to)	39-45
Journal	Materials Science and Engineering A
Volume	610
DOIs	https://doi.org/10.1016/j.msea.2014.05.022
Publication status	Published - 2014

Fields of Expertise

Advanced Materials Science

Access to Document

10.1016/j.msea.2014.05.022

Cite this

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title = "The microstructure of heat-treated nickel-based superalloy 718Plus",

abstract = "The microstructure of thermally aged nickel-based 718Plus superalloy is investigated using transmission electron microscopy (TEM). Solution annealing at 980 °C for 30 min is followed by either the standard quenching to room temperature or quenching directly to 788 °C, before isothermal aging at 788 °C for four hours. Micro-hardness and yield strength are measured to compare the effects of the two variations. The size and phase fraction of γ′ precipitates are measured using dark-field TEM and related to the hardness and yield strength through a theoretical model based on coherency and antiphase boundary effects. A population of very small sub-precipitates is observed and the larger γ′ precipitates are investigated in detail using high resolution scanning TEM to reveal information about the chemical ordering.",

author = "Lawrence Whitmore and Ahmadi, {Mohammad Reza} and Laure Guetaz and Harald Leitner and Erwin Povoden-Karadeniz and Martin Stockinger and Ernst Kozeschnik",

year = "2014",

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language = "English",

volume = "610",

pages = "39--45",

journal = "Materials Science and Engineering A ",

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T1 - The microstructure of heat-treated nickel-based superalloy 718Plus

AU - Whitmore, Lawrence

AU - Ahmadi, Mohammad Reza

AU - Guetaz, Laure

AU - Leitner, Harald

AU - Povoden-Karadeniz, Erwin

AU - Stockinger, Martin

AU - Kozeschnik, Ernst

PY - 2014

Y1 - 2014

N2 - The microstructure of thermally aged nickel-based 718Plus superalloy is investigated using transmission electron microscopy (TEM). Solution annealing at 980 °C for 30 min is followed by either the standard quenching to room temperature or quenching directly to 788 °C, before isothermal aging at 788 °C for four hours. Micro-hardness and yield strength are measured to compare the effects of the two variations. The size and phase fraction of γ′ precipitates are measured using dark-field TEM and related to the hardness and yield strength through a theoretical model based on coherency and antiphase boundary effects. A population of very small sub-precipitates is observed and the larger γ′ precipitates are investigated in detail using high resolution scanning TEM to reveal information about the chemical ordering.

AB - The microstructure of thermally aged nickel-based 718Plus superalloy is investigated using transmission electron microscopy (TEM). Solution annealing at 980 °C for 30 min is followed by either the standard quenching to room temperature or quenching directly to 788 °C, before isothermal aging at 788 °C for four hours. Micro-hardness and yield strength are measured to compare the effects of the two variations. The size and phase fraction of γ′ precipitates are measured using dark-field TEM and related to the hardness and yield strength through a theoretical model based on coherency and antiphase boundary effects. A population of very small sub-precipitates is observed and the larger γ′ precipitates are investigated in detail using high resolution scanning TEM to reveal information about the chemical ordering.

U2 - 10.1016/j.msea.2014.05.022

DO - 10.1016/j.msea.2014.05.022

M3 - Article

SN - 1873-4936

VL - 610

SP - 39

EP - 45

JO - Materials Science and Engineering A

JF - Materials Science and Engineering A

ER -