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Title: Morphology, Microstructure and Residual Stress in EB-PVD Erbia Coatings

Abstract

The electron-beam physical vapor deposition of erbium-oxide coatings onto sapphire wafers is investigated to evaluate processing effects on the residual stress state and microstructure. The erbium-oxide coatings are found to be in a compressive stress state. The crystallographic texture of the erbium-oxide coating is evaluated using X-ray diffraction along with an assessment of forming the cubic erbia phase as a function of substrate temperature. In addition to the cubic erbia phase, an orthorhombic phase is found at the lower deposition temperatures. A transition is found from a two-phase erbium-oxide coating to a single phase at deposition temperatures above 948 K. The variation in morphology with deposition temperature observed in fracture cross-sections is consistent with features of the classic zone growth models for vapor-deposited oxide coatings. For high-temperature applications, a deposition process temperature above 948 K is seen to produce a stoichiometric, fully dense, and equiaxed-polycrystalline coating of cubic erbia.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2]
  1. Lawrence Livermore National Laboratory (LLNL)
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931674
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Materials Science; Journal Volume: 42; Journal Issue: 14
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ERBIUM OXIDES; ENERGY BEAM DEPOSITION; COATINGS; MICROSTRUCTURE; PHYSICAL VAPOR DEPOSITION; SAPPHIRE; SUBSTRATES; TEXTURE; ELECTRON BEAMS; RESIDUAL STRESSES; PHASE STUDIES; TEMPERATURE DEPENDENCE; Erbia; EBPVD; Coating; Residual Stress

Citation Formats

Jankowski, Alan, Saw, C K, Ferreira, J L, Harper, J S, Hayes, J., and Pint, Bruce A. Morphology, Microstructure and Residual Stress in EB-PVD Erbia Coatings. United States: N. p., 2007. Web. doi:10.1007/s10853-006-0658-7.
Jankowski, Alan, Saw, C K, Ferreira, J L, Harper, J S, Hayes, J., & Pint, Bruce A. Morphology, Microstructure and Residual Stress in EB-PVD Erbia Coatings. United States. doi:10.1007/s10853-006-0658-7.
Jankowski, Alan, Saw, C K, Ferreira, J L, Harper, J S, Hayes, J., and Pint, Bruce A. Mon . "Morphology, Microstructure and Residual Stress in EB-PVD Erbia Coatings". United States. doi:10.1007/s10853-006-0658-7.
@article{osti_931674,
title = {Morphology, Microstructure and Residual Stress in EB-PVD Erbia Coatings},
author = {Jankowski, Alan and Saw, C K and Ferreira, J L and Harper, J S and Hayes, J. and Pint, Bruce A},
abstractNote = {The electron-beam physical vapor deposition of erbium-oxide coatings onto sapphire wafers is investigated to evaluate processing effects on the residual stress state and microstructure. The erbium-oxide coatings are found to be in a compressive stress state. The crystallographic texture of the erbium-oxide coating is evaluated using X-ray diffraction along with an assessment of forming the cubic erbia phase as a function of substrate temperature. In addition to the cubic erbia phase, an orthorhombic phase is found at the lower deposition temperatures. A transition is found from a two-phase erbium-oxide coating to a single phase at deposition temperatures above 948 K. The variation in morphology with deposition temperature observed in fracture cross-sections is consistent with features of the classic zone growth models for vapor-deposited oxide coatings. For high-temperature applications, a deposition process temperature above 948 K is seen to produce a stoichiometric, fully dense, and equiaxed-polycrystalline coating of cubic erbia.},
doi = {10.1007/s10853-006-0658-7},
journal = {Journal of Materials Science},
number = 14,
volume = 42,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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