Through-thickness determination of phase composition and residual stresses in thermall barrier coatings using high- energy x-rays.

Journal Article · Thu Jan 01 04:00:00 EST 2009 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2009.10.010· OSTI ID:979554

Weyant, C M; Almer, J D; Faber, K T

High-energy X-rays were used to determine the local phase composition and residual stresses through the thickness of as-sprayed and heat-treated plasma-sprayed thermal barrier coatings consisting of a NiCoCrAlY bond coat and an yttria-stabilized zirconia (YSZ) topcoat produced with through-thickness segmentation cracks. The as-sprayed residual stresses reflected the combined influence of quenching stresses from the plasma spray process, thermal expansion mismatch between the topcoat, bond coat and substrate, and stress relief from the segmentation cracks. Heat treatments led to the formation of a thermally grown oxide (TGO) which was in compression in the plane, as well as relief of quenching stresses and development of a stress gradient in the YSZ topcoat. The high-energy X-ray technique used in this study revealed the effects that TGO and segmentation cracks have on the in-plane stress state of the entire coating.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 979554
• Report Number(s): ANL/XSD/JA-65525
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 3 ; 2009 Vol. 58; ISSN 1359-6454; ISSN ACMAFD
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
CHEMICAL COMPOSITION
CHROMIUM ALLOYS
COBALT ALLOYS
HEAT TREATMENTS
NICKEL ALLOYS
PLASMA ARC SPRAYING
RESIDUAL STRESSES
SPRAYED COATINGS
THERMAL BARRIERS
YTTRIUM ALLOYS
YTTRIUM OXIDES
ZIRCONIUM OXIDES