| The effect of dissimilar metal (1100-0 Al, 6061-T6, 5083-H32, SM15C, SCM2, SCM21, SNCM8, SNCM21, STS304, DIN x10CrNiMoTi1810, Cu, brass, bronze) on the galvanic corrosion of 5086-H116 Al alloy in the synthetic sea water was studied by the galvanic current method and corrosion product morphologies on the 5086-H116 Al alloy exposed in the salt spray test chamber were observed by the metallurgical microscope and scanning electron microscope. Results show that the potential difference of uncoupled dissimilar metals is a poor indicator of the extent(rate) of galvanic corrosion of coupled dissimilar metals. Galvanic series for 5086-H116 Al alloy in synthetic sea water based on the galvanic current density was Cu≥brass>SM15C≥SNCM21≥bronze>SNCM8>SCM2≥SCM21>STS304≥DIN x10CrNiMoTi1810≥6061-T6>1100-0≥5083-H32. Corrosion product morphologies on the 5086-H116 Al alloy exposed in the salt spray test chamber agreed with the galvanic current data. When coupled with other Al alloy there was no galvanic effect but when coupled with Cu, brass, SM15C, pitting and intergranular corrosion occurred on the surface of the 5086-H116 Al alloy near the interface of the dissimilar metal. |
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