Crystallization Behavior of Electroless Co-Ni-B Plating in Magnetic Field in the Presence of Cerium

The electrochemical property, chemical composition and crystal structure of electroless Co-Ni-B-Ce alloy plated in common state as well as in magnetic field were studied by means of potentiometer, plasma transmitting spectrometer, electron energy spectrometer, X-ray diffractometer and transmission electron microscope. The results showed that the static potential and polarizability of electroless Co-Ni-B alloy are remarkably improved as the plating is carried out in magnetic field in the presence of a little amount of cerium in plating bath. The cerium content in the electroless Co-Ni-B-Ce alloy increases at first with the increase of cerium in bath and decreases with maximum value at Ce0.8 g/L in plating baths. Under the action of magnetic field and rare metal cerium, the boron content in alloy is decreased, while cobalt and nickel contents are increased. As a resolut, a amorphous Co-Ni-B alloy is transformed to microcrystalline Co-Ni-B-Ce alloy when plating in is common state, and the latter plated in magnetic field is crystallized.