Chemically deposited Ni-W-B coatings: composition, structure, and properties1.

The effect of temperature and solution components of the chemical catalytic reduction on the composition of Ni-W-B alloy coatings is studied. The x-ray photoelectron spectroscopy in combination with the layer-by-layer profile analysis is used to determine the chemical state of elements and the composition of surface and bulk layers of the coatings containing 28 and 1.8 wt % (10 and 12 at. %) tungsten and boron, respectively. The surface of such coatings is shown to contain up to 90 and 80 at. % reduced nickel and boron, respectively. The deposits have amorphous structure. The effect of thermal treatment conditions on the structure and microhardness of the coatings is investigated. The coatings with a tungsten content of 10 at. % are shown to be nonmagnetic. [ABSTRACT FROM AUTHOR]