海水冷却装置20#碳钢管腐蚀破损分析

应用光学显微镜、电子能谱分析、Ｘ－射线衍射分析和电化学方法对渔船海水冷却装置２０＃碳钢管腐蚀破损事故进行分析，结果表明，产生腐蚀损坏的主要原因是由于材料热处理不当，导致晶粒粗化，出现脱碳层，且处基体中氯离子聚集，引起孔蚀所致。

FAILURE ANALYSIS OF SEAWATER COOLING CHILLER ON 20* CARBON STEEL PIPE

The failure of the seawater chiller made of 20 # carbon steel pipes for fishing vessel was investigated by using optical microscope, EDX, X\|ray diffraction spectra and electrochemical measurements. The results showed that the failure of the pipe was due to pitting corrosion. The corrosion cause was attributed to the improper heat treatment, which can lead to coarse grains and decarburizition, and to the high chloride content measured on the corroded steel pipe. Some measures for protection are proposed.