Skip to main content
main-content
Top

Hint

Swipe to navigate through the articles of this issue

01-06-2015 | Issue 6/2015

Metallurgical and Materials Transactions A 6/2015

Nanoscale Cellular Structures at Phase Boundaries of Ni-Cr-Al-Ti and Ni-Cr-Mo-Al-Ti Superalloys

Journal:
Metallurgical and Materials Transactions A > Issue 6/2015
Authors:
Cong Wang, David C. Dunand
Important notes
Manuscript submitted July 31, 2014.

Abstract

The microstructural evolution of Ni-20 pct Cr wires was studied during pack cementation where Al and Ti, with and without prior cementation with Mo, are deposited to the surface of the Ni-Cr wires and subsequently homogenized in their volumes. Mo deposition promotes the formation of Kirkendall pores and subsequent co-deposition of Al and Ti creates a triple-layered diffusional coating on the wire surface. Subsequent homogenization drives the alloying element to distribute evenly in the wires which upon further heat treatment exhibit the γ + γ′ superalloy structure. Unexpectedly, formation of cellular structures is observed at some of the boundaries between primary γ′ grains and γ matrix grains. Based on additional features (i.e., ordered but not perfectly periodic structure, confinement at γ + γ′ phase boundaries as a cellular film with ~100 nm width, as well as lack of topologically close-packed phases), and considering that similar, but much larger, microstructures were reported in commercial superalloys, it is concluded that the present cellular structure solidified as a thin film, composed of eutectic γ + γ′ and from which the γ′ phase was subsequently etched, which was created by incipient melting of a region near the phase boundary with high solute segregation.

Please log in to get access to this content

To get access to this content you need the following product:

Springer Professional "Wirtschaft+Technik"

Online-Abonnement

Mit Springer Professional "Wirtschaft+Technik" erhalten Sie Zugriff auf:

  • über 69.000 Bücher
  • über 500 Zeitschriften

aus folgenden Fachgebieten:

  • Automobil + Motoren
  • Bauwesen + Immobilien
  • Business IT + Informatik
  • Elektrotechnik + Elektronik
  • Energie + Umwelt
  • Finance + Banking
  • Management + Führung
  • Marketing + Vertrieb
  • Maschinenbau + Werkstoffe
  • Versicherung + Risiko

Testen Sie jetzt 30 Tage kostenlos.

Springer Professional "Technik"

Online-Abonnement

Mit Springer Professional "Technik" erhalten Sie Zugriff auf:

  • über 50.000 Bücher
  • über 380 Zeitschriften

aus folgenden Fachgebieten:

  • Automobil + Motoren
  • Bauwesen + Immobilien
  • Business IT + Informatik
  • Elektrotechnik + Elektronik
  • Energie + Umwelt
  • Maschinenbau + Werkstoffe




Testen Sie jetzt 30 Tage kostenlos.

Literature
About this article

Other articles of this Issue 6/2015

Metallurgical and Materials Transactions A 6/2015 Go to the issue

Premium Partner

    Image Credits