Pulse-plating effects on the properties of nickel and nickel-molybdenum electrodeposits

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5216409

Kim, W

Square-wave cathodic current modulation and periodic-anodic superimposed on cathodic d.c. current were investigated to determine their effects on mechanical properties, structure, and internal stress of nickel and Ni-Mo electrodeposits. The force imposed by an electrobalance which counteracted the bending of a stressed cantilever substrate strip was monitored during deposition and hydrogen charging. The quantity of hydrogen that permeated through a palladium substrate was also measured. The structures of the deposit were studied by transmission and scanning electron microscopy. The higher peak current densities and the accompanying higher over-potentials permitted by pulse plating were found to have resulted in substantial grain refinement and a corresponding increase in strength to double that obtained by d.c. plating. Yield and tensile strengths, which were 730 and 1120 MPa, respectively were attained by pulse plating compared to 360 and 550 MPa, respectively when direct current was used. A reduction of the internal tensile stresses due to pulse plating can be explained by several phenomena.

• Research Organization: Stevens Inst. of Tech., Hoboken, NJ (USA)
• OSTI ID: 5216409
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
CHEMICAL REACTIONS
COATINGS
CRYSTAL STRUCTURE
CURRENT DENSITY
DEPOSITION
ELECTRODEPOSITED COATINGS
ELECTRODEPOSITION
ELECTROLYSIS
ELECTROPLATING
ELEMENTS
HYDRIDATION
LYSIS
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
MOLYBDENUM ALLOYS
NICKEL
NICKEL ALLOYS
PLATING
PULSES
SURFACE COATING
TRANSITION ELEMENTS