elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Stress-induced formation of TCP phases during high temperature low cycle fatigue loading of the single-crystal Ni-base superalloy ERBO/1

Meid, Carla and Eggeler, Mario and Watermeyer, Philipp and Kostka, Aleksander and Hammerschmidt, Thomas and Drautz, Ralf and Eggeler, Gunther and Bartsch, Marion (2019) Stress-induced formation of TCP phases during high temperature low cycle fatigue loading of the single-crystal Ni-base superalloy ERBO/1. Acta Materialia, 168, pp. 343-352. Elsevier. DOI: 10.1016/j.actamat.2019.02.022 ISSN 1359-6454

Full text not available from this repository.

Abstract

The microstructural evolution in the single crystal Ni-base superalloy ERBO/1 (CMSX 4 type) is investigated after load controlled low cycle fatigue (LCF) at 950 °C (load-ratio: 0.6, tensile stress range: 420 -740 MPa, test frequency: 0.25 Hz, fatigue rupture life: about 1000 - 3000 cycles). Bulk topologically close packed (TCP) phase particles precipitated and were analyzed by three-dimensional focus ion beam slice and view imaging and analytical transmission electron microscopy. The particles did not precipitate homogenously but at locations with enhanced levels of local stresses/strains, such as isolated g-channels subjected to cross channel stresses, shear bands and in front of micro cracks. The influence of stress/strain is furthermore apparent in the spatial arrangement and the shape of the TCP phase particles. Only µ-phase TCP particles were found by electron diffraction. Results of a structure-map analysis suggest that most of these TCP particles observed after LCF testing would not precipitate in thermodynamic equilibrium. In order to rationalize this effect, the atomic volume was analyzed that transition-metal (TM) elements take in unary fcc and in unary m-phase crystal structures and found that all TM elements except Zr and V take a larger volume in a unary m phase than in a unary fcc phase. This trend is in line with the observed localized precipitation of TCP phases that are rich in Ni and other late TM elements. The experimental and theoretical findings suggest consistently that formation of TCP particles in LCF tests is considerably influenced by the local tensile stress/strain states.

Item URL in elib:https://elib.dlr.de/128752/
Document Type:Article
Title:Stress-induced formation of TCP phases during high temperature low cycle fatigue loading of the single-crystal Ni-base superalloy ERBO/1
Authors:
AuthorsInstitution or Email of AuthorsAuthors ORCID iD
Meid, CarlaDLR WF (ENM)UNSPECIFIED
Eggeler, MarioDLR WF (ENM)UNSPECIFIED
Watermeyer, PhilippWFUNSPECIFIED
Kostka, AleksanderRuhr-Universität BochumUNSPECIFIED
Hammerschmidt, ThomasRuhr-Universität BochumUNSPECIFIED
Drautz, RalfRuhr-Universitätr BochumUNSPECIFIED
Eggeler, GuntherRuhr-Universität BochumUNSPECIFIED
Bartsch, Marionmarion.bartsch (at) dlr.dehttps://orcid.org/0000-0002-3952-2928
Date:15 February 2019
Journal or Publication Title:Acta Materialia
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In SCOPUS:Yes
In ISI Web of Science:Yes
Volume:168
DOI :10.1016/j.actamat.2019.02.022
Page Range:pp. 343-352
Publisher:Elsevier
ISSN:1359-6454
Status:Published
Keywords:Intermetallic phases, Low cycle fatigue, Ni-base superalloy single crystals, Structure maps, Three-dimensions imaging
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Aeronautics
HGF - Program Themes:propulsion systems
DLR - Research area:Aeronautics
DLR - Program:L ER - Engine Research
DLR - Research theme (Project):L - Virtual Engine and Validation methods
Location: Köln-Porz
Institutes and Institutions:Institute of Materials Research > Experimental and Numerical Methods
Deposited By: Bartsch, Dr.-Ing. Marion
Deposited On:22 Oct 2019 14:44
Last Modified:22 Oct 2019 14:44

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.