Volume 8, Issue 6 (June 2011)
Particle Characterization and Sizing: SEM Utilizing Automated Electron Beam and AFA Software for Particle Counting and Particle Characterization
In recent decades oil analysis laboratories have used automatic particle counters to determine the number and size of particles in many oil wetted systems. Once determined, there has been the question of “what are they?” Logically, the next step is to investigate the make-up of the particles by extracting the particles and analyzing using emission spectroscopy and/or a filter membrane for view them under magnification. Characterizing the make-up of the particles is very useful in determining the source. A cost-effective action plan can be undertaken to rectify the identified problem once the particle type is determined. The problem with these two approaches is; emission spectroscopy analysis is often unreliable in identifying larger particles and; under optical magnification it is not possible to tell for sure the makeup of the particles. In some cases scanning electron microscopy (SEM) analysis is undertaken to further identify the particles. This proves to be time-consuming for the SEM operator and is left to the operator to judge which areas of the sample to investigate. This study illustrates the performance and innovative approach to resolving the aforementioned limitations on sizing and identifying particles using an “Automated Electron Beam Particle Analyzer” equipped with “Automated Feature Analysis” (AFA) software to characterize complex matrix of particles extracted onto a membrane filter from oil samples.