Effect of prolonged thermal cycles on the pitting corrosion resistance of a newly developed LDX 2404 lean duplex stainless steel

The effect of aging temperature on the microstructure and pitting corrosion behavior of a newly developed LDX 2404 lean duplex stainless steel is investigated. The results show that variations of aging temperature affect the pitting corrosion resistance of LDX 2404 due to the formation of precipitates. The preferential zones for the initiation of pits transform from the austenite phase for the as-annealed specimens to the chromium-depleted zones for the aged ones. The pitting corrosion resistance of the aged specimens drops firstly and then increases again with the increase of aging temperature, and the lowest corrosion resistance is exhibited at 800 °C.