Migration of sulphur in thermal barrier coatings during heat treatment
The sulphur effect in thermal barrier coatings (TBCs) mainly refers to a segregation of sulphur at the interface between thermally grown oxide (TGO) and the bond coat, which significantly deteriorates scale adhesion to alloys. Restricted by the extremely low concentrations of sulphur (0-10 ppm) in T...
Main Authors: | , , , , , |
---|---|
Format: | Journal article |
Published: |
Elsevier
2016
|
_version_ | 1826264711099842560 |
---|---|
author | Bai, M Jiang, H Chen, Y Chen, Y Grovenor, C Zhao, X Xiao, P |
author_facet | Bai, M Jiang, H Chen, Y Chen, Y Grovenor, C Zhao, X Xiao, P |
author_sort | Bai, M |
collection | OXFORD |
description | The sulphur effect in thermal barrier coatings (TBCs) mainly refers to a segregation of sulphur at the interface between thermally grown oxide (TGO) and the bond coat, which significantly deteriorates scale adhesion to alloys. Restricted by the extremely low concentrations of sulphur (0-10 ppm) in TBCs, previous investigations using conventional analytical techniques failed to provide a complete mechanism for the migration of sulphur. In this study, high resolution secondary ion mass spectrometry (NanoSIMS) was employed to detect trace sulphur distributions in commercial TBCs. After heat treatments, sulphur segregates at three typical areas in TBCs: (1) the yttria stabilized zirconia (YSZ) top coat; (2) the TGO/bond coat interface and (3) the grit blasted surface. This indicates that during heat treatment a significant outward diffusion of sulphur occurs from the superalloy to YSZ top coat through the TGO, and a possible mechanism for the migration of sulphur in TBCs is described. The undesired "sulphur effect" on scale adhesion was suggested to be caused by the formation of residual sulphides beneath the alumina scale with weaker ionic bonding to alloy cations. Possible solutions are suggested aiming to alleviate the sulphur effect in TBCs. |
first_indexed | 2024-03-06T20:12:14Z |
format | Journal article |
id | oxford-uuid:2af60057-a239-4247-929c-89a009232aca |
institution | University of Oxford |
last_indexed | 2024-03-06T20:12:14Z |
publishDate | 2016 |
publisher | Elsevier |
record_format | dspace |
spelling | oxford-uuid:2af60057-a239-4247-929c-89a009232aca2022-03-26T12:28:09ZMigration of sulphur in thermal barrier coatings during heat treatmentJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:2af60057-a239-4247-929c-89a009232acaSymplectic Elements at OxfordElsevier2016Bai, MJiang, HChen, YChen, YGrovenor, CZhao, XXiao, PThe sulphur effect in thermal barrier coatings (TBCs) mainly refers to a segregation of sulphur at the interface between thermally grown oxide (TGO) and the bond coat, which significantly deteriorates scale adhesion to alloys. Restricted by the extremely low concentrations of sulphur (0-10 ppm) in TBCs, previous investigations using conventional analytical techniques failed to provide a complete mechanism for the migration of sulphur. In this study, high resolution secondary ion mass spectrometry (NanoSIMS) was employed to detect trace sulphur distributions in commercial TBCs. After heat treatments, sulphur segregates at three typical areas in TBCs: (1) the yttria stabilized zirconia (YSZ) top coat; (2) the TGO/bond coat interface and (3) the grit blasted surface. This indicates that during heat treatment a significant outward diffusion of sulphur occurs from the superalloy to YSZ top coat through the TGO, and a possible mechanism for the migration of sulphur in TBCs is described. The undesired "sulphur effect" on scale adhesion was suggested to be caused by the formation of residual sulphides beneath the alumina scale with weaker ionic bonding to alloy cations. Possible solutions are suggested aiming to alleviate the sulphur effect in TBCs. |
spellingShingle | Bai, M Jiang, H Chen, Y Chen, Y Grovenor, C Zhao, X Xiao, P Migration of sulphur in thermal barrier coatings during heat treatment |
title | Migration of sulphur in thermal barrier coatings during heat treatment |
title_full | Migration of sulphur in thermal barrier coatings during heat treatment |
title_fullStr | Migration of sulphur in thermal barrier coatings during heat treatment |
title_full_unstemmed | Migration of sulphur in thermal barrier coatings during heat treatment |
title_short | Migration of sulphur in thermal barrier coatings during heat treatment |
title_sort | migration of sulphur in thermal barrier coatings during heat treatment |
work_keys_str_mv | AT baim migrationofsulphurinthermalbarriercoatingsduringheattreatment AT jiangh migrationofsulphurinthermalbarriercoatingsduringheattreatment AT cheny migrationofsulphurinthermalbarriercoatingsduringheattreatment AT cheny migrationofsulphurinthermalbarriercoatingsduringheattreatment AT grovenorc migrationofsulphurinthermalbarriercoatingsduringheattreatment AT zhaox migrationofsulphurinthermalbarriercoatingsduringheattreatment AT xiaop migrationofsulphurinthermalbarriercoatingsduringheattreatment |