中央空调用钢管失效分析

Failure Analysis of Steel Pipe Used in Central Air Conditioning

研究了中央空调用钢管的失效。中央空调用钢管在安装使用一段时间后,出现泄漏。通过宏观检查、金相组织分析、化学成分检测、扫描电子显微镜及能谱分析等方法,分析了中央空调用钢管泄漏的机理和原因。结果表明,钢管泄漏的主要原因是氯离子吸附在钢管内表面形成点蚀核,并逐渐向深处扩展,最终在自催化作用下造成钢管被腐蚀穿透。

In this paper,the failure of steel pipe used in central air conditioning was investigated.Leakage was observed in the pipeline during operation.Macroscopic analysis,metallurgical structure inspection,chemical composition analysis,scanning electron microscope（SEM） and energy dispersion spectrum（EDS） analysis were carried out to investigate the leakage mechanism and cause.The results revealed that the adsorption of chloride ion on the internal surface of steel pipe caused the nucleation of pitting.The corrosion cell leaded to deepening of the pitting.Finally,the self-catalyzed reaction leaded to the leakage failure of the steel pipe.