Electrical resistivity of electroless nickel coated carbon fibers

Variation of electrical resistivity of electroless nickel-coated carbon fib ers heat-treated at different temperatures was investigated. The electrical resistivity was measured using the single fiber technique. Measurement res ults showed that as the heat treatment temperature increased, the resistivi ty decreased to a temperature of approximately 300 degreesC. A further incr ease of heat treatment temperature up to 450 degreesC, however, resulted in an increase of resistivity. Structural study using X-ray diffraction indic ated that a large proportion of Ni3P is formed only above 300 degreesC, whi ch is responsible for the increase of resistivity. Also, the increase of re sistivity was found to be more pronounced and occurs at lower temperatures for samples with higher phosphorous content. (C) 2001 Elsevier Science B.V. All rights reserved.