High-Strength Nanocrystalline Ni-W Alloys Produced by Electrodeposition


Nanocrystalline Ni-W alloys having both high ductility and high strength were produced by electrodeoisition. The plating bath for the electrodeposition contained nickel sulfate, citric acid, sodium tungstate and ammonium chloride, and was operated at various bath concentrations and conditions of electrolysis. The ductility and tensile strength of the deposited alloys are strongly influenced by inclusion of codeposited hydrogen during deposition process. After degassing the hydrogen, the high-strength nanocrystalline Ni-W alloy containing about 20.7 at. % W with an average grain size of about 3 nm has been obtained: the tensile strength attained to about 2300 MPa. The high ductility of this alloy was also observed: bending through an angle of 180 degree was possible without breaking