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Porous TiNi Synthesis from Elemental Powders

Published online by Cambridge University Press:  16 February 2011

Janet C. Hey
Affiliation:
Dept. of Materials Science & Engineering, SUNY at Stony Brook, Stony Brook, NY 11794-2275
A. Peter Jardine
Affiliation:
Dept. of Materials Science & Engineering, SUNY at Stony Brook, Stony Brook, NY 11794-2275
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Abstract

The shape memory alloy TiNi is produced by either Vacuum Induction Melting (VIM) or by Vacuum Arc Remelting (VAR) of pure metal ingots for actuator applications. Powder metallurgy techniques provide an alternative fabrication route for their use in passive damping applications where porosity and deviations in chemical homogeneity can be tolerated. In this study TiNi compacts were cold pressed from the blended elemental powders and sintered in vacuum for varying times at temperatures from 800°C to 1000°C. Two heating rates were used, 5 K/min. and 10 K/min. A TiNi microstructure could be produced after annealing at 1000°C for 6 h., although some TiNi3 was still observed. Sintering above 900°C produced porous microstructures with green densities approaching 3.5 gm/cm3.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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References

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