Influence of composition on the thermal behavior of chemically deposited nickel-phosphorus alloys

The thermal behavior of Ni-P [95509-07-2] alloys contg. 6-22 at.%P obtained by electroless deposition from chloride-glycollate solns. at different pH values was studied by using DSC and x-ray diffraction. The alloys are microcryst. or partially amorphous, depending on the P content. Near 773 K, the amorphous phase is transformed into an equil. mixt. of Ni and Ni3P. Most of the alloys crystallize in 2 exothermic stages. The alloys with near-eutectic compns. are te only ones crystg. in 1 stage. The 1st thermal effect in hypoeutectic alloys is due to pptn. of Ni crystallites from the primary amorphous phase and/or growth of pre-existing solid-soln. grains. The 2nd effect is due to crystn. of the intermediate amorphous phase into Ni3P + Ni. The 1st stage of crystn. in hypereutectic alloys corresponds to the formation of randomly oriented Ni3P, while in the 2nd stage the residual amorphous phase yields the eutectic. [on SciFinder(R)]