Corrosion of AISI stainless steels is governed by the stability, composition, and repairability of their chromiumrich passive films. Although stainless steels are widely recognized for their corrosion resistance, localized forms of attack, particularly pitting, crevice corrosion, intergranular corrosion, erosion-corrosion, and stress-corrosion cracking, can occur under aggressive chemical, thermal, mechanical, or electrochemical conditions. These processes present significant challenges in petroleum refining, chemical processing, construction, transportation, power generation, food processing, marine systems, and water treatment. Corrosion can cause material failure, economic losses, environmental contamination, and safety hazards. Among the available corrosion-control techniques, corrosion inhibitors can reduce metal dissolution and stabilize protective surface films when their chemistry is compatible with the stainless-steel grade and service environment. This review discusses the fundamental principles of corrosion inhibition with special reference to AISI stainless steels, including the electrochemical mechanisms of passive-film formation and breakdown, major forms of localized corrosion, classification of corrosion inhibitors, and the physicochemical factors governing inhibitor performance. Particular attention is given to AISI 304 and AISI 316 stainless steels, chloride-induced pitting and crevice corrosion, organic and inorganic inhibitors, adsorption-based protection, repassivation, and environmentally sustainable alternatives derived from plant extracts, biopolymers, and other renewable resources. Methods for evaluating inhibition performance, including gravimetric analysis, open-circuit potential measurements, potentiodynamic polarization, cyclic polarization, electrochemical impedance spectroscopy, critical pitting temperature measurements, and surface characterization, are examined. Thermodynamic adsorption models and computational approaches are also discussed. Finally, the major challenges associated with long-term stability, environmental compatibility, reproducibility, galvanic coupling, and industrial application are identified. The review emphasizes that effective corrosion inhibition of AISI stainless steel requires an integrated understanding of passive-film chemistry, electrochemical kinetics, interfacial adsorption, alloy metallurgy, and environmental conditions.

Prof .Dr. Udai Arvind, "Corrosion and Its Inhibition in AISI Stainless Steel: Mechanisms, Electrochemical Evaluation, and Sustainable Approaches" International Journal of Advance Research in Science, Management, Engineering and Technology, V1(4): Page(110-121) September - October 2026. ISSN: 3139-1141. www.ijarsmet.com. Published by Scientific and Academic Research Publishing.