Quantitative texture analysis in pulse reverse current electroforming of nickel

The crystallographic texture of nickel deposits is known to be related to its magnetic and mechanical properties. However, up to now, most of the texture analyses of electrodeposited nickels have been semi-quantitative and still use a nickel sulphate bath, which is mainly for decorative industrial applications. In this paper, a quantitative texture analysis using ODF (orientation distribution function) has been carried out to study the effect of a pulse reverse current on the crystallographic texture of electroformed nickels, with the use of a nickel sulphamate bath, which is now commonly used for functional industrial applications and micro-or precise components. It was found that the [100] fibre texture with different orientation densities was formed at different on-times and off-times. With a constant off-time of 0.5 ms, an increase in on-time led to a gradual decrease in the orientation density of the [100] texture, whereas with a constant on-time of 5 ms, an increase in off-time has affected the change of the orientation density of the [100] texture in a more complicated manner. All of these phenomena are considered to be related to the change of the amount of inhibiting chemical species such as nickel hydroxide adsorbed on the cathode surface and the nickel deposition rate.