Characterization of vickers hardness and corrosion rate of stainless steel-316L coated with hydroxyapatite-polyvinyl alcohol

Abstract

Abstract This study aims to determine the effect of variations in the composition of the hydroxyapatite-Poly Vinyl Alcohol (HA-PVA) coating to the Vickers hardness and the corrosion rate of SS316L. Cylindrical stainless steel-316L (SS316L), which has a diameter of 8mm and a thickness of 5mm, was sterilized by immersion in ethanol then rinsed using distilled water. The coating material is made from a mixture of HA-PVA with variations in the composition of A (27: 3), B (25: 5), C (20:10) and D (15:15) (in wt%) dissolved in 70% distilled water (in wt%). HA-PVA solution was coated on SS316L using airbrush spraying method at a pressure of 3.5x105 Pa, a nozzle diameter of 0.4 mm and a nozzle-sample distance of 10 cm. The test results show that the variations of the HA-PVA composition affect the hardness and the corrosion rate of SS316L. The more HA coating on the SS316L, the more it protects the SS316L substrate from corrosion. The conclusion show that the sample A with the HA-PVA composition of 27: 3 (in wt%) is found to be the best composition with a Vickers hardness of 2.43 VHN and a corrosion rate of 0.004 mm/year.