Intermetallic Matrix Composites by Physical Vapor Deposition

AbstractThe feasibility of producing layered composite sheet material, in which the matrix is the intermetallic compound TiAl, using physical vapor deposition (PVD) has been demonstrated. The PVD techniques of sputtering and electron beam evaporation were both investigated. Films were deposited by alternately sputtering from targets of composition Ti-53A1–3Nb and TiB2 or were co-deposited from separate electron beam heated hearths containing Ti and Al. In the latter case, nitrogen gas was pulsed into the deposition chamber at controlled intervals resulting in the formation of a TiAl/TiAlN layered composite. The composition of the films was determined using Auger analysis and Rutherford backscattering spectroscopy and the crystal structure was checked using X-ray and electron diffraction. Cross-sections through the films were prepared for examination by transmission electron microscopy so that the layered microstructure of the films could be verified.

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Metastable phase evolution in Al2O3 dispersed nanocrystalline NiCr alloys

Journal of Materials Research ◽

10.1557/jmr.2007.0004 ◽

2007 ◽

Vol 22 (1) ◽

pp. 68-75 ◽

Cited By ~ 1

Author(s):

Dheepa Srinivasan ◽

P.R. Subramanian

Keyword(s):

Electron Beam ◽

High Temperature ◽

Grain Growth ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Metastable Phase ◽

Phase Evolution ◽

Free Energies ◽

Alumina Particles ◽

The Matrix

The high temperature structural stability of nanograined NiCr alloys reinforced with nanoscale yttria and alumina dispersoids, fabricated by electron beam physical vapor deposition (EBPVD), was examined. The yttria particles coarsened very little and also inhibited grain growth in the matrix successfully, whereas the alumina dispersoids coarsened rapidly and were not as effective in restricting matrix grain growth. A hierarchy of phase transformations took place in the Al2O3 particles present as nano dispersoids in a nanograined NiCr matrix , on annealing. Coarsening of the alumina particles was accompanied by these phase transitions. The phase evolution is attributed to differences in free energies between the metastable and stable phases and a kinetic hierarchy in nucleation, brought about by structural and hence interfacial energy considerations.

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Delamination of Electron-Beam Physical-Vapor Deposition Thermal Barrier Coatings using Luminescent Layers

AIAA Scitech 2021 Forum ◽

10.2514/6.2021-0432 ◽

2021 ◽

Author(s):

Quentin P. Fouliard ◽

Ranajay Ghosh ◽

Seetha Raghavan

Keyword(s):

Electron Beam ◽

Thermal Barrier Coatings ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Thermal Barrier ◽

Barrier Coatings

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Titanium carbide coatings deposited by reactive ion beam-assisted, electron beam–physical vapor deposition

Surface and Coatings Technology ◽

10.1016/s0257-8972(99)00644-1 ◽

2000 ◽

Vol 124 (2-3) ◽

pp. 142-153 ◽

Cited By ~ 40

Author(s):

Douglas E. Wolfe ◽

Jogender Singh

Keyword(s):

Electron Beam ◽

Titanium Carbide ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Ion Beam ◽

Carbide Coatings

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Strain Tolerance and Microstructure of Thermal Barrier Coatings Produced by Electron Beam Physical Vapor Deposition Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.522-523.267 ◽

2006 ◽

Vol 522-523 ◽

pp. 267-276 ◽

Cited By ~ 1

Author(s):

Kunihiko Wada ◽

Yutaka Ishiwata ◽

Norio Yamaguchi ◽

Hideaki Matsubara

Keyword(s):

Electron Beam ◽

High Temperature ◽

Thermal Barrier Coatings ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Aging Treatment ◽

Nanoindentation Test ◽

Thermal Barrier ◽

Barrier Coatings ◽

Strain Tolerance

Several kinds of thermal barrier coatings (TBCs) deposited by electron beam physical vapor deposition (EB-PVD) were produced as a function of electron beam power in order to evaluate their strain tolerance. The deposition temperatures were changed from 1210 K to 1303 K depending on EB power. In order to evaluate strain tolerances of the EB-PVD/TBCs, a uniaxial compressive spallation test was newly proposed in this study. In addition, the microstructures of the layers were observed with SEM and Young’s moduli were measured by a nanoindentation test. The strain tolerance in as-deposited samples decreased with an increase in deposition temperature. In the sample deposited at 1210 and 1268 K, high-temperature aging treatment at 1273 K for 10 h remarkably promoted the reduction of the strain tolerance. The growth of thermally grown oxide (TGO) layer generated at the interface between topcoat and bondcoat layers was the principal reason for this strain tolerance reduction. We observed TGO-layer growth even in the as-deposited sample. Although the thickness of the initial TGO layer in the sample deposited at high temperature was thicker, the growth rate during aging treatment was smaller than those of the other specimens. This result suggests that we can improve the oxidation resistance of TBC systems by controlling the processing parameters in the EB-PVD process.

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