Study of low-alloy steels resistant to marine corrosion
In research conducted by the ECSC and IRSID over several years, it has proved possible to define low-alloy steel compositions offering improved resistance to marine corrosion (base 2% chromium, 1% aluminium, 0.3% molybdenum). The aim of the programme was to obtain a better technological mastery of these grades by : a) optimising the chemical composition of chromium- and aluminium-alloyed steels b) studying welding conditions and the mechanical properties and corrosion resistance of the welds c) studying the influence of nickel additions (up to 1%) on corrosion behaviour in tidal and splash zones. The results show that the production and working of the grades studied pose no particular problems. These steels can be welded by several processes (arc, MIG, TIG) without particular precautions. However, use of a low-alloy filler metal is recommended, in order to minimise the risk of electric coupling between the parent metal and the weld, observed in submerged and tidal zones. Under these conditions the weld offers no particular sensitivity to hydrogen embrittlement. Nickel has a favourable effect on marine corrosion resistance in splash zones. Aluminium and chromium appreciably reduce the corrosion kinetics in the submerged zones while the addition of molybdenum reduces the occurrence of pitting. On the basis of these results, a standard chemical composition offering a good technical/economic compromise is proposed.
Bibliographic Reference: EUR 11426 FR (1988)
Record Number: 198910038 / Last updated on: 1994-12-01
Original language: fr
Available languages: fr