Development of Electrodeposition Bath Using a Substitute of Propionic Acid for Bulk Nanocrystalline Ni-W Alloys with High Ductility

Abstract

A substitute for propionic acid, which is a complexing agent in the Ni W electrodeposition process for producing bulk nanocrystalline alloys with high ductility, was explored. Bulk nanocrystalline Ni W alloys were electrodeposited using electrolyte that primarily consisted of nickel sulfamate and sodium tungstate with sodium propionate and/or sodium gluconate. Their W content, impurity contents, microstructure, and mechanical properties were investigated. The Ni W alloys electrodeposited from conventional bath exhibited tensile strength of 1.66 GPa and elongation of 6.5. Substitution of propionic acid by sodium propionate enhanced tensile elongation up to 11.3 along with high strength of 1.65 GPa. Also, substitution by sodium gluconate enhanced tensile strength up to 1.80 GPa with elongation of 5.2. The results of this study demonstrate that the propionic acid in the Ni W electrodeposition process can be replaced by sodium propionate without property degradation.

Comparison of Tensile Properties of Bulk Nanocrystalline Ni–W Alloys Electrodeposited by Direct, Pulsed, and Pulsed-Reverse Currents

“…3(a)) exhibited a nanocrystalline structure with a grain size of approximately 30 nm. The microstructures of the Ni-W alloys, prepared with the use of pulsed currents, are consistent with results obtained with the use of direct currents in previous reports 31,32) . Conversely, the sample PRC 0.2_20 (Fig.…”