1996 Volume 45 Issue 5 Pages 572-576
Ni-P alloy film was electrodeposited at 5-232A·dm-2 on an alumina substrate by using the electroplating apparatus equipped with a high flow rate circular pump. With increasing current density, the current efficiency for the deposition on Ni-P decreased once. When the current efficiency was minimum, the P content in the film obtained in the electrolytes with various pH was always 7.5wt%. In the X-ray diffraction profile of Ni-P film with 7.5wt% P content, (200) diffraction peak disappeared and only (111) peak became strong. The overpotential of hydrogen evolution on the Ni-P film with 7.5wt% P content became minimum. The current efficiency, P content, crystal structure and overpotential of hydrogen evolution were closely related one another. TCR of Ni-P alloy film was correlate with its P content.
