Effect of laser surface texturing and boriding on the tribocorrosion resistance of an ASTM F-1537 cobalt alloy

Different kinds of materials are broadly employed to manufacture bioimplants. Metals are commonly used for the fabrication of lower body components such as knee prostheses and hip replacements because of their good mechanical properties. Among the available metallic biomaterials, cobalt alloys are commonly used. However, the hostile environment of the human body promotes the corrosion of the metallic bioimplant, and the wear due to the sliding contact could also increase the corrosion. There is, therefore, a constant attempt to study the surface of metallic biomaterials to enhance their functionality. In the present work, two kinds of surface modification techniques were employed on ASTM F-1537 cobalt alloy samples: laser surface texturing and boriding. Tribocorrosion tests were carried out using a linear reciprocating tribometer coupled with a standard three-electrode electrochemical cell. Tafel polarization plots were used to calculate the material loss due to corrosion. Also, non-contact profilometry was employed to estimate the tribocorrosion volume loss. In addition, the worn tracks were analyzed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The textured + borided samples increased 1.5 times the tribocorrosion resistance compared to the untreated samples. The differences in the tribocorrosion performance among the modified surfaces were discussed in this paper.