Influence of Electrolytes on the Galvanic corrosion of Copper-Aluminum Couples

• Main Authors: Chin-Cheng Lai, 賴信成
• Other Authors: Liu-Ho Chiu
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/34111460759219665875

碩士 === 大同大學 === 材料工程學系(所) === 94 === The corrosion rates of metals in water cooling system were studied in this research by using electrochemical method. The copper and aluminum alloy couples were immersed in different electrolytes to simulate water cooling system environment, in addition to, the corrosion potential and corrosion current destiny was also obtained by a polarization test. Furthermore, the galvanic corrosion current of coupled copper and aluminum specimen was measured by a zero resistance ammeter, and the surface morphology of corroded specimen was observed by a scanning electron microscope to clarify the damage effect caused by the electrochemical reaction. The results showed that the corrosion rate of aluminum sheet specimen is faster than that of copper sheet protected in the galvanic corrosion phenomena of Cu and Al sheet couple. The AA6063-C1100 couple in the corrosion inhibitor (F) had lowest galvanic corrosion current densities was 3.4×10-7 A/cm2 among this investigation. The addition of the inhibitor (F) also retarded the corrosion reaction when the electrolyte was heated to 70oC. However, the corrosion rates were greatly be increase in the sodium chloride solution. Key words: galvanic corrosion, copper-aluminum couples