Huang, Han-ShengHan-ShengHuangChien, Wei-LiangWei-LiangChienCHAO-SUNG LIN2026-01-152026-01-152025-12https://www.scopus.com/record/display.uri?eid=2-s2.0-105023988735&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/735341HSLA-80 steel is commonly used in marine applications due to its superior strength, toughness, good weldability, and atmospheric corrosion resistance. Inconel-625 alloy, which exhibits outstanding corrosion resistance and high-temperature strength, is a preferred choice for pipes in highly corrosive environments. This study investigated the corrosion behavior of HSLA-80 and Inconel-625 dissimilar weldments fabricated by multi-pass fusion welding using an electrode with a composition similar to Inconel-625. HSLA-80 steel was composed of quasipolygonal ferrite. The heat-affected zone (HAZ) on HSLA-80 steel consisted of primary ferrite, bainite, and martensite/austenite constituents. Electrochemical tests in 0.6 M NaCl solution revealed that the corrosion susceptibility decreased in the order of HSLA-80 > fusion zone ≃ Inconel-625. Moreover, the HAZ of HSLA-80 steel and Inconel-625 had inferior corrosion resistance compared to their base metals. The dissimilar weldment underwent a corrosion rate of 212.8 mils per year (mpy) after 88 days of immersion in 0.6 M NaCl solution. The corrosion rate of the as-received HSLA-80 steel evaluated by polarization curves was 1.6 mpy. Consequently, the corrosion of the HSLA-80 HAZ was accelerated by macro- and micro-galvanic coupling effects.trueCorrosionGalvanic couplingHigh-strength low-alloy steelMulti-pass fusion weldingNickel-based superalloyjournal article10.1016/j.rineng.2025.1080182-s2.0-105023988735