Comparison of the corrosion resistance of DIN W. Nr. 1.4970 (15%Cr-15%Ni-1.2%Mo-Ti) and ASTM F-138 (17%Cr-13%Ni-2.5%Mo) austenitic stainless steels for biomedical applications

Abstract

The resistance to localised corrosion of the full austenitic 15%Cr-15%Ni-1.2%Mo titanium stabilized stainless steel (DIN W. Nr. 1.4970) was investigated by electrochemical methods including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and potentiostatic polarization measurements in a phosphatebuffered solution (PBS). The low carbon and non-stabilized austenitic stainless steel, AISI 316L (ASTM F-138), widely used for surgical implants, was also tested for comparison. The tests were conducted at room temperature after a stable potential had been reached. After the electrochemical measurements, the surfaces of the specimens were observed using SEM to evaluate the presence of pits. Potentiodynamic polarization results showed that both steels are prone to localized corrosion. Larger pits were found on the surface of AISI 316L specimens after the electrochemical tests. EIS response has indicated the duplex structure of the passive oxides. The results showed that the electrochemical behaviour of the DIN W. Nr. 1.4970 is better than of AISI 316L steel. Therefore, their application as an implant material may be considered.

The effect of shot peening on fatigue and corrosion behavior of 316L stainless steel in Ringer's solution

“…The dynamic features of oxide film are the key factors of high corrosion resistance of stainless steels in corrosive environments. In addition, the presence of Molybdenum in 316L stainless steel increases the resistance to pitting corrosion in saline environments [7].…”

“…Despite these problems, stainless steel implants are still currently used due to a combination of corrosion resistance, mechanical strength, ductility, toughness and easy fabrication at low cost [7]. Survey of failed stainless implants indicates that majority of failure in 316L SS implants is because of pitting or crevice corrosion, fatigue and wear [5,8,9].…”

Use of SECM to study the electrochemical behavior of DIN 1.4575 superferritic stainless steel aged at 475 °C

“…Ti and Ti alloys are by far the most used materials for body implants; however, their excessive prices make them unaffordable to the health public system of underdeveloped countries. Thus researches on biocompatibility and corrosion resistance on simulating body fluid solutions of less expensive materials are under way in many countries [1,2]. Milosev and Strehblow [3] studied the corrosion behavior of stainless steels in a physiological solution and concluded that the properties of the passive layer, account for the corrosion resistance of orthopedic implants produced with these materials.…”

Complex Material and Surface Analysis of Anterolateral Distal Tibial Plate of 1.4441 Steel

“…Once more, a 60 min time gap was applied between the two polarizations. Each polarization test was terminated when the value of corrosion current density reached 2 × 10 −3 A/cm −2 , which ensured that the material was located in a transpassive state and the surface was actively corroded [11].…”