A study on the wear resistance characteristics of pulse electroforming Ni–P alloy coatings as plated

• Published in: Wear Vol. 262; no. 7; pp. 833 - 844
• Main Authors: Hou, Kung-Hsu, Jeng, Ming-Chang, Ger, Ming-Der
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.03.2007; Amsterdam Elsevier Science; New York, NY
• Subjects: Applied sciences; Contact of materials. Friction. Wear; Exact sciences and technology; Friction, wear, lubrication; Machine components; Mechanical engineering. Machine design; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Ni–P alloy coatings; Pulse electroforming; Wear resistance; Ni–P alloy coatings; Wear resistance; Pulse electroforming; Nickel base alloys; Wear test; Electrocrystallization; Amorphous state; Metal; Phosphorus alloys; Steel; Hardness; Experimental study; Optimization; Lubricant; Crystalline material; Metal coating; Internal stress; Abrasive wear; Morphology; Ni-P alloy coatings; Electrodeposition; Room temperature; Crystalline structure; Tribology
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/j.wear.2006.08.023

In this study, attempt has been initiated to investigate the wear resistance of Ni–P alloy coatings manufactured by pulse current (PC) electroforming technology. The wear tests of such plated coatings were carried out at ambient temperature and without lubricants. The parameters of the electroforming experiments include peak current density, duty cycle and pulse frequency. The results of this investigation showed that the internal stress of the PC-deposited Ni–P coating is much lower than that of direct current (DC) deposited Ni–P coating. The analytical results indicate that increasing of the phosphorus content in the layer reduces the hardness of the Ni–P electroformed coatings, and it gradually leads to transformation of the coatings structure from micro-crystalline to nano-crystalline/X-ray amorphous. Wear trace morphology shows that the wear mechanism of Ni–P coatings herein is related to hardness. As the hardness increases, the worn morphology of the coatings changes from with scratches and abrasions to that with the steel debris adhered on the coatings. The wear resistance of Ni–P alloy electroformed layers increases with the hardness of the coatings. The hardness primarily affects the wear resistance of the Ni–P as plated coatings, and the optimum wear resistance of Ni–P coatings can reach 11 times that of Ni coatings.