空调换热器铜管失效分析

Failure Analysis of Copper Tubes of in Heat Exchanger of Air Conditioner

对空调运行过程中冷却铜管发生腐蚀穿孔的情况进行失效分析。采用金相显微镜、扫描电镜对腐蚀失效的铜管进行微观组织观察和局部元素成分分析。结果表明,铜管内壁含有大量的Fe3+,与铜管表面氧化膜及铜基体反应,内壁表面垢层存在一定量的Cl-、Br-以及SO42-,这些离子进一步促进了铜管腐蚀穿孔。

The failure analysis of the corrosion and perforation of the cooling copper pipe during the operation of the air conditioner was carried out. The metallographic microscope and scanning electron microscope were used to observe the microstructure and analyze the local element composition of the corroded copper tube. The results showed that there were a lot of Fe3+ in the inner wall of copper tube, which reacted with the oxide film and copper matrix on the surface of copper tube. There were a certain amount of Cl-, Br-and SO42-in the scale layer on the inner wall, which further promoted the corrosion and perforation of copper tube.