The nickel–phosphorous (Ni–P) coating on carbon
fiber was studied, using sodium hypophosphite as a reducing agent in alkaline medium. The effects of process parameters such as
time, stabilizer concentrations, pH of the plating bath and plating bath’s temperature on the
electroless Ni–P coating efficiency were investigated. Structural study using X-ray diffraction
(XRD) indicates that nickel deposition rate increases with increasing coating time and
temperature. The nickel (Ni) recovery efficiency decreases with an increase of stabilizer concentration.
From scanning electron microscopy (SEM) and energy dispersive X-ray analysis
(EDX), it has been confirmed that the coating thickness and nickel content increase with
an increase of coating time and temperature. The bath temperature of 25 ◦C, pH of 9, and
stabilizer concentration of 25 g/L is good to get a good and uniform coating of Ni on carbon
fiber. Thermal stability was studied by thermogravimetric analysis (TGA) and differential
thermal analysis (DTA). From TGA study it is evident that the nickel coating increases thermal
stability of the nickel-coated carbon fiber. I–V (current vs voltage) measurement shows
Ni-coated fiber is more conducting in nature.
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