Effect of porosity on electrical conductivity of hot pressed AlN ceramic
نویسندگان
چکیده
2014 Temperature dependence of electrical conductivity has been studied for hot pressed AlN ceramic having different volume percentage of porosity (0.2 to 15 %) in the temperature range (500 K to 950 K). It has been observed that electrical conductivity decreases by two orders of magnitude as the volume percentage of porosity increases from 0.2 to 15 %. The effect of moisture on electrical conductivity has also been studied on the same samples of AlN. Samples having small porosity (upto 4 volume %) did not show any appreciable effect of moisture on electrical conductivity. However, at higher concentration of porosity (15 volume %), the conductivity increases by three orders of magnitude after exposing to the moisture. Tome 21 ? 9 SEPTEMBRE 1986 Revue Phys. Appl. 21 (1986) 525-529 SEPTEMBRE 1986, .
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