Electroless deposited Ni-Re-P, Ni-W-P and Ni-Re-W-P alloys

Coatings of electroless Ni-W-P, Ni-Re-P and Ni-W-Re-P alloys were plated in alkaline citrate baths containing amino alcohols, but not free ammonia ions. The reference Ni-P alloy was used as an intermediate layer in the sandwich: Ni-Me-P/Ni-P/substrate. An extremely homogeneous thickness distribution of all alloy components was found by applying scanning Auger electron spectroscopy (SAES). The inclusion of refractory metals at the expense of nickel and without substantial change in phosphorus content was established. A non-oxidized state of the codeposited Re and W in Ni-W-P, Ni-Re-P and Ni-W-Re-P alloys was determined by means of X-ray photoelectron spectroscopy examination, as well as by SAES profiles, revealing the absence of oxygen throughout the coatings. All alloy films are amorphous and paramagnetic.