发动机磁性检屑器异常表面分析

航空发动机新机交付装机时,发现辅助齿轮箱下磁性检屑器铝合金表面异常,检屑器孔口及内部液体中出现大量白色物质.通过对磁性检屑器异常表面形貌观察、能谱分析、化学滴定法分析确认了磁性检屑器异常表面属碱性介质引起的腐蚀,腐蚀产物为Na、Al形成的盐类物质,以及Al、Mg形成的Al(OH)₃、Mg(OH)₂的混合物.通过滑油分析、发动机装配情况调查、APC-Ⅰ型水基清洗剂成分分析及加速模拟试验,证明造成磁性检屑器发生腐蚀的介质为装配时进入齿箱的APC-Ⅰ型水基清洗剂.

Analysis of Abnormal Surface of Magnetic Chip Detector in Engine

The aluminium alloy surface of the magnetic chip detector in an aero-engine was found to be abnormal after installation. There was much white material in the porthole and internal liquid. The morphology, energy spectrum analysis, and chemical titration were carried out. The results show that the abnormal surface was caused by corrosion from alkali media, and the corrosion products were saline minerals with Na and Al and mixture including Al（OH）3 and Mg（OH）2. Through analyzing the lube, surveying engine assembly, analyzing composition of the APC-I water base cleaning agent and performing simulation test, it was found the APC-I water base cleaning agent caused the corrosion on the surface of the engine magnetic chip detector.