Publication detail

Microstructural instability of L-PBF Co-28Cr-6Mo alloy at elevated temperatures

ROUDNICKÁ, M. MOLNÁROVÁ, O. DRAHOKOUPIL, J. ŠREIBR, V. PALOUŠEK, D. VOJTĚCH, D.

Original Title

Microstructural instability of L-PBF Co-28Cr-6Mo alloy at elevated temperatures

Type

journal article in Web of Science

Language

English

Original Abstract

In relation to the production of complex aircraft components, the additive manufacturing (AM) of Co-28Cr-6Mo alloy is highly discussed as it could bring many benefits regarding new designs, components lightening and shortening the design-to-product period. However, such components must undergo strict requirements for mechanical properties and material stability, even at elevated temperatures which might occur during part operation. So far, little is known about the thermal stability of Co-28Cr-6Mo alloy when produced by laser powder bed fusion (L-PBF), one of the mostly used AM technologies. In the present study, we reveal the instability of this material already at temperatures above 673 K. Material hardening accompanied with a significant loss of plasticity is caused by the breakdown of fine cellular microstructure with intercellular Mo segregation, precipitation of sigma-phase and phase transformation of the matrix. Detail characterization by transmission electron microscopy was carried out for the maximum hardness state obtained after annealing the alloy at 1173 K for 5 h. The important findings of this study, representing an operational risk for L-PBF Co-28Cr-6Mo alloy, call for subsequent research into suitable heat treatment that would induce the stability of the material.

Keywords

Co-28Cr-6Mo; Additive manufacturing; Laser powder bed fusion; Elevated temperature operation

Authors

ROUDNICKÁ, M.; MOLNÁROVÁ, O.; DRAHOKOUPIL, J.; ŠREIBR, V.; PALOUŠEK, D.; VOJTĚCH, D.

Released

15. 5. 2021

Publisher

ELSEVIER

Location

AMSTERDAM

ISBN

2214-7810

Periodical

Additive Manufacturing

Year of study

44

Number

44

State

Kingdom of the Netherlands

Pages from

1

Pages to

16

Pages count

16

URL

http://www.sciencedirect.com/science/article/pii/S2214860421001901?via%3Dihub

BibTex

@article{BUT175115,
  author="Orsolya {Molnárová} and Jan {Drahokoupil} and Vít {Šreibr} and David {Paloušek} and Dalibor {Vojtěch} and Michaela {Roudnická}",
  title="Microstructural instability of L-PBF Co-28Cr-6Mo alloy at elevated temperatures",
  journal="Additive Manufacturing",
  year="2021",
  volume="44",
  number="44",
  pages="1--16",
  doi="10.1016/j.addma.2021.102025",
  issn="2214-7810",
  url="http://www.sciencedirect.com/science/article/pii/S2214860421001901?via%3Dihub"
}