This paper reports on a structural characterisation of the nickel alloy coatings, before and after the fuse process is done and the main phases in each case, showing important differences between the nickel alloy coatings. Spray and fuse process involves thermal spraying to apply a coating of special self-fluxing alloys and a post thermal treatment at temperature between the solidus and liquidus of the alloy, when important diffusion processes take place. An improvement of the hardness and tribological properties is observed with the addition of tungsten carbide-cobalt to the nickel alloy powder. The results show the excellent tribological properties of the spray and fused coatings, better than the obtained for the as-sprayed coatings. The adhesion strength of the nickel alloy coating after the thermal treatment achieve a value above 80 MPa. Paper includes a German-language abstract.