Electrodeposited Ni-B alloy films: Preparation and structural aspects

Abstract

The formation of Ni-B alloy films by electrodeposition route and evaluation of their structural characteristics, phase transformation behavior and corrosion resistance are discussed. The Ni-B alloy films were prepared using Watt's nickel bath containing dimethylamine borane (DMAB) as the source of boron. The ratio of rate of reduction of nickel and rate of decomposition of DMAB determines the boron content of the films. The Ni-B films electrodeposited in the current density range of 1-4 A/dm(2) are found to be crystalline in their as-plated condition and annealing at 623 K, 1 h results in redistribution of nickel. The phase transformation behavior of electrodeposited Ni-B films reveals that the energy evolved during transformation is very low and the peak temperature is around 573-633 K. The corrosion resistance of electrodeposited Ni-B coatings is higher than electrodeposited nickel.