A method to monitor non-ferrous debris in ferrographic analysis

Abstract

Non-ferrous debris in oil sample provide important information about the wear condition of a wear couple containing non-ferrous metal components. In order to collect wear debris of non-ferrous metal material more effectively and deposit them on a ferrogram in a stable depositing ratio, the method of employing magnetic fluid as a magnetization agent to collect non-ferrous wear debris in ferrography was attempted. Magnetic fluid constituting Fe3O4 magnetic particles was prepared using a precipitation reaction. Tetrachloroethylene was used as a carrier liquid to ensure that magnetic fluid can be easily mixed with lubricant oil sample. Oleic acid was used as a surfactant, which enables magnetic particles to adhere to the surface of non-ferrous wear debris. Then the non-ferrous wear debris was magnetized and deposited on a ferrogram in a stable depositing ratio. Copper debris was chosen as an example of non-ferrous debris to illustrate the magnetization effect of the magnetic fluid. With the help of magnetic fluid, the ferrographic analyst will achieve the operating condition of the machine more accurately.