HIGH-STRENGTH NANOCRYSTALLINE Ni-W ALLOYS PRODUCED
Department of Materials Science & Engineering, Faculty of Engineering,
Himeji Institute of Technology, 2167 Shosha, Himeji, Hyogo 671-2201, Japan.
TEL: +81-792-66-1661, FAX: +81-792-66-8868
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.
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