关键词: 电化学, 腐蚀, 经济, 海水, 污水, 换热设备, 模糊综合评价法

Abstract: Currently,the researches on metal corrosion are mostly focused on factors which affect the corrosion and the anticorrosion technology. The literature on metal corrosion economy of heat exchanger is comparatively less. This paper adopted the loss of mass experiment by hanging metal specimen and the SEM analysis to study the self-corrosion rate and galvanic-corrosion rate of carbon steel 10^#,copper T2,stainless steel 316L and aluminum alloy LF21 in sea water and sewage respectively as well as the micro corrosion morphology. In addition,the use of fuzzy synthetic evaluation method provides the basis for selecting metal materials of heat-exchange equipment reasonably. The results show that copper T2,stainless steel 316L and aluminum alloy LF21 are all corrosion-resisting metal,and stainless steel 316L has the best corrosion resistance in both static and flowing water environment. Aluminum alloy LF21 is more corrosion-resistant than carbon steel 10^# and copper T2 as long as it is not in a galvanic couple strictly. It is excellent on both corrosion resistance and economy. Although carbon steel 10^# is poor in corrosion resistance,it is the most common metal material in the actual project because of its better economical benefits.

Key words: electrochemistry, corrosion, economics, sea water, sewage, heat-exchange equipment, fuzzy synthetic evaluation