Abstract
“ACTE” (Accelerated corrosion test for electrical appliances) is an accelerated corrosion and consists of salt deposition process and cyclic process in which absolute humidity is constant. This accelerated corrosion test is useful for sufficient evaluation of surface-treated steel. In this study, improvement of “ACTE” was performed to evaluate atmospheric corrosion for aluminum alloys. In this improved “ACTE” for Al alloys (“Al-ACTE”), temperature/relative humidity of wet or dry conditions were selected as 20°C/95%RH or 35°C/40%RH respectively. These conditions were derived from measurements of actual environments and were decided to avoid the formation of passive film in oxidation conditions. Exposure time of cyclic wet/dry process was selected as 4 hours for a cycle. “Al-ACTE” for ADC12 and A1100 was compared with exposure tests of Miyakojima-shielded and Chyoshi-shielded from the view point of depth of pitting. The acceleration ratio of “Al-ACTE” against the atmospheric exposure tests was calculated. It was found that the depth of pitting of A1100 was more affected by the amount of deposited-salt than that of ADC12. This dependence in Al-ACTE showed the same tendency as the atmospheric exposure tests.
“Al-ACTE” makes it possible to appropriately evaluate the corrosion resistance on aluminum alloys by considering the amount of deposited salt.
