The formation of a heterogeneous oxidized layer, also called scale, on metallic surfaces is widely recognized as a rapid manufacturing event for metals and their alloys. Partial or total removal of the scale represents a mandatory integrated step for the industrial fabrication processes of medical devices. For biodegradable metals, acid pickling has already been reported as a preliminary surface preparation given further processes, such as electropolishing. Unfortunately, biodegradable medical prototypes presented discrepancies concerning acid pickling studies based on samples with less complex geometry (e.g., non-uniform scale removal and rougher surface). Indeed, this translational knowledge lacks a detailed investigation on this process, deep characterization of treated surfaces properties, as well as a comprehensive discussion of the involved mechanisms. In this study, the effects of different acidic media (HCl, HNO3, H3PO4, CH3COOH, H2SO4 and HF), maintained at different temperatures (21 and 60 °C) for various exposition time (15–240 s), on the chemical composition and surface properties of a Fe–13Mn-1.2C biodegradable alloy were investigated. Changes in mass loss, morphology and wettability evidenced the combined effect of temperature and time for all conditions. Pickling in HCl and HF solutions favor mass loss (0.03–0.1 g/cm2) and effectively remove the initial scale.
Biodegradable metallic alloys are promising materials for the development of temporary medical implants, including cardiovascular and orthopedic devices. The present work explores the surface modification of a biodegradable Fe–20Mn alloy by means of ultrashort laser texturing and the correlation between the laser‐induced surface morphology and the degradation behavior. In detail, the effect of different processing parameters on surface morphology is explored and compared with the unprocessed surface. It is found that laser texturing can tune the degradation rate, selectively inducing positive (+29%) or negative (−31%) change with respect to the untreated surface.
20 December 2024 in Journal of Materials Research and Technology