Corrosion and wear resistance of tin bronze and five commonly used iron-carbon alloys in simulated seawater

The ship's anchor chain rings， sliding bearings， and other components exposed to seawater are subjected to long-term corrosion and wear， collectively referred to as tribocorrosion. The tricoborrosion resistance of these materials directly affects the operational safety of marine equipment. In this study， the in-situ electrochemical testing method for corrosion and wear are employed to investigate the tribocorrosion resistance of six commonly used materials in artificial seawater environments： anchor chain steel （CM690）， bearing steel （GCr15）， high-strength marine steel （AH36 steel）， cast iron for diesel engine cylinder liners （HT350）， tin bronze for plain bearing bushings （QSn8）， and steel most commonly used in mechanical structures （45 steel）. The objective is to analyze their corrosion resistance and damage resistance mechanisms. The results show that under pure corrosion conditions， QSn8 exhibits a significantly higher self-corrosion potential compared to other iron-carbon alloys， and has the lowest corrosion rate （0.09 mm/a）. However， under corrosion wear conditions， HT350 demonstrates a relatively low wear loss rate （6.28×10-6 mm³/（N·m））， second only to QSn8 （3.47×10-6 mm³/（N·m））. This is attributed to its high hardness and the lubricating effect of graphite flakes within the cast iron matrix. The other four materials exhibits higher wear rates，around （1.22-1.88）×10-5 mm³/（N·m）. QSn8 shows excellent resistance to both corrosion and wear in simulated seawater conditions， making it a promising candidate for tribocorrosion-resistant components. However， its relatively high cost may limit its widespread application. If other mechanical performance requirements are met， HT350 can serve as a cost-effective alternative.