Constrasting and Optical Constants of Carbides and Borides in Wear Resistant Co- and Ni-base Alloys.

The optical constants of various phases in hard Co- and Ni-base alloys were determined by the use of interference coating microscopy. The range of the refractive index and absorption coefficient of the borides is such that it separates them clearly in optical terms both from the previously determined carbides and nitrides, on the one hand, as well as from the sulfides and oxides, on the other. The conditions are given under which a good light-dark contrast and color contrast can be made between the various carbides and borides in wear-resistant materials.