Quantitative analysis for the microstructure of lithium-based grease: Methodology and application

The advancement of image processing technology has introduced novel approaches for material structural analysis. This study develops a quantitative analysis method for the microstructure of lithium-based greases utilizing ImageJ. The SEM images of grease fibers are firstly pre-processed in order to enhance the accuracy of calculation. Then the void fraction in the fiber network is obtained through threshold and area calculation. The average fiber diameter and length are calculated via local thickness analysis and skeleton analysis, respectively. Additionally, this method was applied to assess the microstructural changes in lithium grease under conditions of intense mechanical shearing and high temperature. The possible reasons for the deterioration of grease performance are also discussed.