No Cover Image

Journal article 665 views 101 downloads

Microstructural evolution of a delta containing nickel-base superalloy during heat treatment and isothermal forging

P.M. Mignanelli, N.G. Jones, K.M. Perkins, M.C. Hardy, H.J. Stone, Karen Perkins Orcid Logo

Materials Science and Engineering: A, Volume: 621, Pages: 265 - 271

Swansea University Author: Karen Perkins Orcid Logo

  • 1-s2.0-S0921509314013252-main.pdf

    PDF | Version of Record

    Copyright 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/)

    Download (3.02MB)

Abstract

The next generation of aerospace gas turbine engines need to operate at higher temperatures and stresses to improve their efficiency and reduce emissions. These operating conditions are beyond the capability of existing nickel-base superalloys, requiring the development of new high temperature mater...

Full description

Published in: Materials Science and Engineering: A
ISSN: 0921-5093
Published: 2015
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa19496
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: The next generation of aerospace gas turbine engines need to operate at higher temperatures and stresses to improve their efficiency and reduce emissions. These operating conditions are beyond the capability of existing nickel-base superalloys, requiring the development of new high temperature materials. Controlling the microstructures of these new materials is key to obtaining the required properties and, therefore, it is critical to understand how these alloys respond to processing and heat treatment. Here, the microstructural evolution of V207M, a new δ containing, nickel-base superalloy, has been investigated following heat treatment and forging. The solvus temperatures of the γ′ and δ phases, determined by differential scanning calorimetry and microscopy, were found to be ~985 and ~1060 °C respectively. Isothermal forging of the alloy was conducted at 1000, 1050 and 1100 °C, corresponding to different volume fractions of retained δ. Considerable softening was observed prior to steady state flow when forging at 1000 °C, whilst only steady state flow occurred at 1050 and 1100 °C. The steady state flow process was believed to be dominated by dynamic recovery in the γ phase, with an activation energy of 407 kJmol−1. Samples that exhibited flow softening also showed a significant change in the orientation of the δ precipitates, preferentially aligning normal to the forging axis, and this reorientation was thought to be the cause of the observed flow softening.
Item Description: & 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/3.0/).
College: College of Engineering
Start Page: 265
End Page: 271