Corrosion of 3003 aluminum alloy in deoxidized water

Corrosion test of AIN99 (99.99% pure aluminum) and A3003 (Al-Mn Alloy) in deoxidized (O2 <0.1 ppm) pure water was conducted at the different temperatures. Although the incubation period, from the beginning of the test until the corrosion rate dramatically increased, was varied depending on temperature, it was not affected much by the composition of the material. It was also found that the corrosion rate changed remarkably depending on the temperature and the composition of the material after the incubation period; the corrosion rate of AIN99 was about three times faster than that of A3003. This was not caused by the speed of reaction of aluminum and water on the aluminum surface. AIN99 corroded all over the surface, while A3003 corrodes partially because Mn and Cu are distributed and the corroded area is small. However, the amount of corrosion was almost the same at the saturated condition, whereas the corrosion rate changes depending on the temperature and the composition of the material. This was because the corrosion continued until corrosion products accumulate to the same level on the surface. Accordingly, it become clear that when corrosion rate was fast, corrosion time was short; on the: other hand, corrosion time was long when corrosion rate was slow.