Abstract(s) :
(Anglais) Electroless nickel-boron coatings exhibit excellent mechanical properties; thus, they are considered prominent candidates to replace the hard chrome. However, commercially available NiB coatings contain a small amount of toxic heavy metals such as Tl and Pb employed as a stabilizing agent, which limits their applications. Those elements are present in the plating solution to stabilize the plating bath and regulate the plating rate.
Recent researches have allowed the development of new toxic-free bath formulations, and one of them is a bath free of stabilizer. It was designed in our laboratory through the adjustment of the complexing agent and pH regulator concentration.
In this work, the properties of the resulting NiB coatings are investigated.
The new coating exhibits properties close to those of the conventional electroless NiB coatings, but noticeably, they present a much-improved corrosion resistance. Besides, it is still possible to improve their properties by post-treatments, such as heat treatment.