Effect of duplex coating (VC–VN) on forming mandrel for better wear resistance

Abstract

The present work aims at investigating the collective function of thermo-reactive diffusion (TRD) and plasma-nitriding duplex coating (vanadium carbide (VC) and vanadium nitride (VC-VN)) on the wear resistance of AISI M2 axial-forming mandrel. TRD process was carried out in molten salt bath furnace at 1020 ± 25°C for 5-6 h and the samples were subjected to vacuum heat treatment process at 1150°C, followed by plasma-nitriding for 1 h at 550°C. Wear properties were examined by subjecting the VC and VC-VN-coated samples to wear test (pin on disc) at normal and elevated temperature (50°and 150°C) with lubrication. Phase composition, surface morphology and elemental mapping were studied through X-ray diffractometer, SEM and EDS analyses, respectively. Study found that the wear resistance of VC-coated samples was higher than VC-VN-coated samples and wear mechanisms for VC and VC-VN coated specimens were assessed to be abrasive and abrasive-oxidative in nature, respectively.

Effect of alkali cleaning for Ni-P-based metallic glass coating on bearing surface

“…Compatible coating on the bearing component surface can be applied to enhance the bearing functions such as promoting a longer service life in actual application. Different types of coatings like metallic [1][2][3][4], organic [5][6][7][8], phosphate [9], chromate [4], oxide [2,[10][11][12][13] on the bearing surfaces have been established to get some functional properties like protection against corrosion up to a great extent. Extensive research work has been done globally on black oxide coating [10][11][12][13] for bearing steel component surface.…”