Comparison of tribological and corrosion characteristics of AISI 316Ti and AISI 430 stainless steels

This study presents an investigation into the tribological, corrosion, and tribocorrosion properties of AISI 316Ti (austenitic) and AISI 430 (ferritic) stainless steels. The comparative analysis focuses on microstructural characterization, hardness, and a series of tribological, electrochemical, and tribocorrosion tests conducted in 0.9% NaCl using a specialized linear tribometer to reveal the quality of the studied materials in tribocorrosion applications. Friction tests were performed under both dry and corrosive conditions, while tribocorrosion tests were conducted under open circuit potential (OCP) conditions in 0.9% NaCl, with the electrode potential of the test specimen monitored during friction. To evaluate the electrochemical behavior of the materials, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were conducted using a 0.9% NaCl solution. The measured corrosion potential (Ecorr) suggests that AISI 430 is thermodynamically more stable than AISI 316Ti; however, AISI 316Ti demonstrated higher polarization resistance (RP) values compared to AISI 430. The findings indicate that material qualities significantly influence the coefficient of friction (CoF). Additionally, a notable antifriction effect of 0.9% NaCl was observed during tribological testing, resulting in a lower CoF compared to dry friction conditions. A cathodic shift in OCP during tribocorrosion testing was also observed in both materials, indicating an increase in corrosion vulnerability when the passive layer is degraded.