Thick nickel electroplating on the surface of electrolessly deposited nickel–phosphorus–boron alloy on quartz optical fiber

Watt electroplating solution was used to prepare a thick nickel deposit on the surface of electroless Ni–P–B alloy coated quartz optical fiber. The effects of the nickel sulfate, sodium dodecyl sulfate, current density and lanthanum oxide on nickel deposition rate and coating quality were studied and their suitable values were determined to be 180 g/L, 0.08 g/L, 0.8 A/dm2, and 0.9 g/L, respectively. Scanning electron microscopy and stereomicroscope were employed to characterize and analyze the surface morphology of the deposit. The results showed that lanthanum oxide helps reduce grain size and improve compactness and microhardness of the Ni coating. The prepared Ni deposit has a thickness of 840 μm, microhardness of 334 HV, resistivity of 21 μΩ·cm, densification degree of 96.4% and wetting time of 2 s.