Abstract
A composite microstructure consisting of small α-al2O3particles dispersed in a β-NiAl coating matrix was synthesized by chemical vapor deposition (CVD). While the surface of a pure Ni substrate was being reacted with AICI3and H2 to form β-NiAl at a temperature of 1050 °C, the partial pressure of CO2in the reactor was controlled via pulsing to nucleate and disperse 50 to 500 nm α-Al2O3particles in the β-NiAl matrix. The relative amount of the α-Al2O3phase increased with coating thickness as the rate of the β -NiAl formation decreased with time. These experimental observations suggest that the synthesis of a graded composite microstructure by the CVD method is feasible.
| Original language | English |
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| Pages (from-to) | 3000-3002 |
| Number of pages | 3 |
| Journal | Journal of Materials Research |
| Volume | 10 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 1 1995 |
Funding
This research was sponsored by the Advanced Gas Turbine Systems Program, Office of Industrial Technologies, U.S. Department of Energy, under Contract DE-ACOS-840R2 1400 with Martin Marietta Energy Systems, Inc., and also in part by the appointment of one of the authors (YWB) to the Oak Ridge National Laboratory Postdoctoral Research Associates Program administered jointly by the Oak Ridge National Laboratory and the Oak Ridge Institute for Science and Education. The authors thank Tom Geer for metallography, Dave Braski for the AES analysis, and Pete Tortorelli and Thomas Watkins for reviewing the manuscript.