TY - JOUR
T1 - Characterization and microhardness of Ni-W-P coatings electrodeposited with gluconate bath
AU - Mahalingam, Dinesh K.
AU - Bera, Parthasarathi
N1 - KAUST Repository Item: Exported on 2021-07-14
Acknowledgements: The authors wish to thank the Director, CSIR−National Aerospace Laboratories for the permission to publish this work. We thank Head, Surface Engineering Division, CSIR−National Aerospace Laboratories for his constant support. Authors thank Dr. K. S. Rajam for her support in designing the project. Help received from Dr. Seenivasan, Mr. Ganesh, Mr. Praveen, Mr. Siju, and Mr. Manikandanath is greatly acknowledged.
PY - 2020
Y1 - 2020
N2 - Ni−W−P coatings are electrodeposited from an acid gluconate bath and the effect of P addition to deposits is characterized by various physicochemical techniques. The effect of direct current (DC) and pulse current (PC) deposition modes on the structure, morphology, surface roughness, and elemental oxidation states of Ni−W−P coatings is studied in detail. X-ray diffraction (XRD) patterns of Ni−W−P coatings display the formation of an amorphous structure, which is influenced by the addition of phosphorus. Results obtained from field emission scanning electron microscopy (FESEM) images reveal the appearance of homogeneous coarse nodular morphology for electrodeposited Ni−W−P coatings devoid of cracks. X-ray photoelectron spectroscopy (XPS) studies of Ni−W−P coatings indicate the presence of metallic and oxidized Ni species in DC-plated coatings, whereas oxidized Ni species dominate in PC-plated coatings. Microhardness of as-deposited DC Ni−W−P coatings increases as the phosphorus content increases, whereas the microhardness is similar for all PC Ni−W−P coatings. The effect of heat treatment on the structure and microhardness of the deposits carried at different temperatures shows a substantial increase in microhardness which is comparable with hard chromium coating.
AB - Ni−W−P coatings are electrodeposited from an acid gluconate bath and the effect of P addition to deposits is characterized by various physicochemical techniques. The effect of direct current (DC) and pulse current (PC) deposition modes on the structure, morphology, surface roughness, and elemental oxidation states of Ni−W−P coatings is studied in detail. X-ray diffraction (XRD) patterns of Ni−W−P coatings display the formation of an amorphous structure, which is influenced by the addition of phosphorus. Results obtained from field emission scanning electron microscopy (FESEM) images reveal the appearance of homogeneous coarse nodular morphology for electrodeposited Ni−W−P coatings devoid of cracks. X-ray photoelectron spectroscopy (XPS) studies of Ni−W−P coatings indicate the presence of metallic and oxidized Ni species in DC-plated coatings, whereas oxidized Ni species dominate in PC-plated coatings. Microhardness of as-deposited DC Ni−W−P coatings increases as the phosphorus content increases, whereas the microhardness is similar for all PC Ni−W−P coatings. The effect of heat treatment on the structure and microhardness of the deposits carried at different temperatures shows a substantial increase in microhardness which is comparable with hard chromium coating.
UR - http://hdl.handle.net/10754/670179
UR - https://linkinghub.elsevier.com/retrieve/pii/S2468023020307616
UR - http://www.scopus.com/inward/record.url?scp=85097751591&partnerID=8YFLogxK
U2 - 10.1016/j.surfin.2020.100769
DO - 10.1016/j.surfin.2020.100769
M3 - Article
SN - 2468-0230
VL - 22
SP - 100769
JO - Surfaces and Interfaces
JF - Surfaces and Interfaces
ER -