Equilibrium relationships between thermal barrier oxides and silicate melts

David L. Poerschke; Talia L. Barth; Carlos G. Levi

doi:10.1016/j.actamat.2016.08.077

Equilibrium relationships between thermal barrier oxides and silicate melts

David L. Poerschke, Talia L. Barth, Carlos G. Levi

Chemical Engineering and Materials Science

Research output: Contribution to journal › Article › peer-review

76 Scopus citations

Abstract

The phase equilibria between thermal barrier coating (TBC) materials and calcium–magnesium–aluminosilicate melts (CMAS, representing deposits formed when siliceous debris is ingested into modern turbine engines), were investigated at 1300 °C. The primary goal was to understand the influence of the deposit and thermal barrier oxide compositions on the melt solubility limits and reaction product constitution. Model deposit compositions with SiO₂ to CaO ratios from 1.4 to 4.7 and with or without MgO were reacted with yttria- and gadolinia-zirconia thermal barrier oxides ranging from pure ZrO₂ to the pure yttria and gadolinia. The reactions formed various crystalline silicate phases; rare earth–calcium–silicate apatite and zircon (ZrSiO₄) were observed most frequently. Following the reactions, the residual melts were depleted in SiO₂ and generally enriched in CaO, MgO, and Al₂O₃. The implications of the anticipated changes in the melt viscosity and the cation partitioning between the melt and various solid solution phases on the efficacy of degradation-mitigating crystallization reactions are discussed.

Original language	English (US)
Pages (from-to)	302-314
Number of pages	13
Journal	Acta Materialia
Volume	120
DOIs	https://doi.org/10.1016/j.actamat.2016.08.077
State	Published - Nov 1 2016

Bibliographical note

Funding Information:
This investigation was supported by the Office of Navy Research under STTR Phase II N00014-12-M-0340 (with Questek Innovations), and ONR grant N00014-16-1-2702 , both monitored by Dr. David Shifler. The work made use of the MRL Shared Experimental Facilities supported by the MRSEC Program of the NSF under Award No. DMR 1121053 ; a member of the NSF-funded Materials Research Facilities Network ( www.mrfn.org ). The funding agencies were not involved in the study design, the collection, analysis and interpretation of the data, or the decision to publish. The authors are grateful to Drs. G.G.E Seward, E. Zaleski, and R.W. Jackson (UCSB) for helpful discussions and assistance EPMA measurements, preparing the CMAS powders, and performing FactSage calculations, respectively.

Publisher Copyright:
© 2016

Keywords

CMAS
Phase equilibria
Rare earth
Solid solution
Thermal barrier coatings (TBC)

Publisher link

10.1016/j.actamat.2016.08.077

Find It

Find It at U of M Libraries

Cite this

@article{42cb1e0e63b5421fb445fd78a44b76ed,

title = "Equilibrium relationships between thermal barrier oxides and silicate melts",

abstract = "The phase equilibria between thermal barrier coating (TBC) materials and calcium–magnesium–aluminosilicate melts (CMAS, representing deposits formed when siliceous debris is ingested into modern turbine engines), were investigated at 1300 °C. The primary goal was to understand the influence of the deposit and thermal barrier oxide compositions on the melt solubility limits and reaction product constitution. Model deposit compositions with SiO2 to CaO ratios from 1.4 to 4.7 and with or without MgO were reacted with yttria- and gadolinia-zirconia thermal barrier oxides ranging from pure ZrO2 to the pure yttria and gadolinia. The reactions formed various crystalline silicate phases; rare earth–calcium–silicate apatite and zircon (ZrSiO4) were observed most frequently. Following the reactions, the residual melts were depleted in SiO2 and generally enriched in CaO, MgO, and Al2O3. The implications of the anticipated changes in the melt viscosity and the cation partitioning between the melt and various solid solution phases on the efficacy of degradation-mitigating crystallization reactions are discussed.",

keywords = "CMAS, Phase equilibria, Rare earth, Solid solution, Thermal barrier coatings (TBC)",

author = "Poerschke, {David L.} and Barth, {Talia L.} and Levi, {Carlos G.}",

note = "Funding Information: This investigation was supported by the Office of Navy Research under STTR Phase II N00014-12-M-0340 (with Questek Innovations), and ONR grant N00014-16-1-2702 , both monitored by Dr. David Shifler. The work made use of the MRL Shared Experimental Facilities supported by the MRSEC Program of the NSF under Award No. DMR 1121053 ; a member of the NSF-funded Materials Research Facilities Network ( www.mrfn.org ). The funding agencies were not involved in the study design, the collection, analysis and interpretation of the data, or the decision to publish. The authors are grateful to Drs. G.G.E Seward, E. Zaleski, and R.W. Jackson (UCSB) for helpful discussions and assistance EPMA measurements, preparing the CMAS powders, and performing FactSage calculations, respectively. Publisher Copyright: {\textcopyright} 2016",

year = "2016",

month = nov,

day = "1",

doi = "10.1016/j.actamat.2016.08.077",

language = "English (US)",

volume = "120",

pages = "302--314",

journal = "Acta Materialia",

issn = "1359-6454",

publisher = "Elsevier Limited",

}

TY - JOUR

T1 - Equilibrium relationships between thermal barrier oxides and silicate melts

AU - Poerschke, David L.

AU - Barth, Talia L.

AU - Levi, Carlos G.

N1 - Funding Information: This investigation was supported by the Office of Navy Research under STTR Phase II N00014-12-M-0340 (with Questek Innovations), and ONR grant N00014-16-1-2702 , both monitored by Dr. David Shifler. The work made use of the MRL Shared Experimental Facilities supported by the MRSEC Program of the NSF under Award No. DMR 1121053 ; a member of the NSF-funded Materials Research Facilities Network ( www.mrfn.org ). The funding agencies were not involved in the study design, the collection, analysis and interpretation of the data, or the decision to publish. The authors are grateful to Drs. G.G.E Seward, E. Zaleski, and R.W. Jackson (UCSB) for helpful discussions and assistance EPMA measurements, preparing the CMAS powders, and performing FactSage calculations, respectively. Publisher Copyright: © 2016

PY - 2016/11/1

Y1 - 2016/11/1

N2 - The phase equilibria between thermal barrier coating (TBC) materials and calcium–magnesium–aluminosilicate melts (CMAS, representing deposits formed when siliceous debris is ingested into modern turbine engines), were investigated at 1300 °C. The primary goal was to understand the influence of the deposit and thermal barrier oxide compositions on the melt solubility limits and reaction product constitution. Model deposit compositions with SiO2 to CaO ratios from 1.4 to 4.7 and with or without MgO were reacted with yttria- and gadolinia-zirconia thermal barrier oxides ranging from pure ZrO2 to the pure yttria and gadolinia. The reactions formed various crystalline silicate phases; rare earth–calcium–silicate apatite and zircon (ZrSiO4) were observed most frequently. Following the reactions, the residual melts were depleted in SiO2 and generally enriched in CaO, MgO, and Al2O3. The implications of the anticipated changes in the melt viscosity and the cation partitioning between the melt and various solid solution phases on the efficacy of degradation-mitigating crystallization reactions are discussed.

AB - The phase equilibria between thermal barrier coating (TBC) materials and calcium–magnesium–aluminosilicate melts (CMAS, representing deposits formed when siliceous debris is ingested into modern turbine engines), were investigated at 1300 °C. The primary goal was to understand the influence of the deposit and thermal barrier oxide compositions on the melt solubility limits and reaction product constitution. Model deposit compositions with SiO2 to CaO ratios from 1.4 to 4.7 and with or without MgO were reacted with yttria- and gadolinia-zirconia thermal barrier oxides ranging from pure ZrO2 to the pure yttria and gadolinia. The reactions formed various crystalline silicate phases; rare earth–calcium–silicate apatite and zircon (ZrSiO4) were observed most frequently. Following the reactions, the residual melts were depleted in SiO2 and generally enriched in CaO, MgO, and Al2O3. The implications of the anticipated changes in the melt viscosity and the cation partitioning between the melt and various solid solution phases on the efficacy of degradation-mitigating crystallization reactions are discussed.

KW - CMAS

KW - Phase equilibria

KW - Rare earth

KW - Solid solution

KW - Thermal barrier coatings (TBC)

UR - http://www.scopus.com/inward/record.url?scp=84984801424&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84984801424&partnerID=8YFLogxK

U2 - 10.1016/j.actamat.2016.08.077

DO - 10.1016/j.actamat.2016.08.077

M3 - Article

AN - SCOPUS:84984801424

SN - 1359-6454

VL - 120

SP - 302

EP - 314

JO - Acta Materialia

JF - Acta Materialia

ER -

Equilibrium relationships between thermal barrier oxides and silicate melts

Abstract

Bibliographical note

Keywords

Publisher link

Find It

Other files and links

Fingerprint

Cite this