A Facile Method to Modify the Characteristics and Corrosion Behavior of 304 Stainless Steel by Surface Nanostructuring toward Biomedical Applications

Abstract

The study addresses how surface nanostructuring of AISI 304 stainless steel (SS) by surface mechanical attrition treatment (SMAT) influences its characteristic properties and corrosion behavior in Ringer's solution. SMAT of 304 SS induced plastic deformation, enabled surface nanocrystallization, refined the grain size, transformed the austenite phase to strain induced α'-martensite phase, increased the surface roughness, induced defects/dislocations, imparted compressive residual stresses at the surface, decreased the contact angle, and increased surface energy. The change in properties of 304 SS following treatment using 5 and 8 mm ⌀ balls for 15, 30, 45, and 60 min has caused a deleterious influence on its corrosion resistance in Ringer's solution, while an improvement in corrosion behavior is observed for those treated using 2 mm ⌀ balls. The increase in surface roughness, transformation of the austenite to α'-martensite phase, a higher extent of deformation, and the presence of larger number of defects/dislocations are main factors responsible for the lower corrosion resistance observed for 304 SS treated using 5 and 8 mm ⌀ balls in Ringer's solution. In spite of having these attributes with a relatively lower extent, 304 SS treated using 2 mm ⌀ balls offered a better corrosion resistance and exhibits a better passivity. For those treated using 2 mm ⌀ balls, the ability of the nanocrystalline surface to promote passivation outweighs the deleterious influences caused by the limited amount of deformation and defects/dislocations. Based on the findings of this study, it is recommend that SMAT of 304 SS using 2 mm ⌀ balls for 15-30 min is the optimum condition to achieve the suitable surface profile, surface characteristics with better corrosion resistance.

Direct Growth of Hexagonal Boron Nitride Nanofilms on Stainless Steel for Corrosion Protection

“…Qualitatively, the h-BN-coated sample exhibits a stronger resistance against corrosion than bare stainless steel. 35 Overall, the obtained EIS results follow a similar tendency of the polarization curves.…”

“…As is well known, such porelike features may act as diffusion channels for corrosive ions into the steel substrate over time, consequently degrading the anticorrosion performance. 35 A subsequent increase in the rf sputtering power will lead to a gradual diminishment of these porelike features. In other words, the films become densified at elevated sputtering powers.…”

“…As E corr is a measure of corrosion susceptibility, the larger shift the corrosion potential toward the noble side, the stronger inhibition the corrosion occurs. 35 Therefore, the ss304 shows stronger resistance against corrosion from the 3.5% NaCl solution after being coated with h-BN nanofilms.…”

The benefits of k-Carrageenan-gelatin hybrid composite coating on the medical grade stainless steel (SS304) used as anticorrosive barrier

“…Such biopolymers, like k-Carrageenan can form complexes with metals by several active O donors in its heterocyclic rings which eventually shield metal surface from contact to corrosive medium [9]. Stainless steel 304 is widely used in many sectors of industry due to its high corrosion resistance and reusability [10]. The medicinal grade stainless steel is commonly employed as biomaterial in orthopaedic implants.…”

Enhanced Pitting Corrosion Resistance of 304 SS in 3.5 wt% NaCl by Ultrasonic Nanocrystal Surface Modification

“…15,[20][21][22][23][24][25][26][27] However, it is still controversial whether SMAT treatment enhances or diminishes the corrosion performance of the treated materials. Hao * Electrochemical Society Member.…”