Dimensional stability of brake pads reinforced with calcined eggshell particles under exposed to engine lubricating oil

Exposure to a humid environment can affect the behavior of brake lining composites. Considering the vital function of brake linings in controlling vehicle speed, environmental influences must receive serious attention. Exposure to lubricating oil that sticks to the brake lining can cause changes in performance during work. This study will investigate the dimensional stability of brake pad composites when exposed to engine oil and understand the physical behavior of material to facilitate appropriate handling. The brake pads in this study comprised 35% phenolic resin, 10% graphite, 10% bamboo fiber, 10% alumina powder, 5% zinc powder, 5% bamboo particles, and 25% eggshell particles. The manufacturing of brake linings involves three process stages: cold compaction, hot compaction, and post-curing. The samples were soaked in Federal Ultratec API SJ JASO MA engine lubricating oil for 12, 24, 36, and 48 hours. The results showed that the immersion time of the composite in lubricating oil did not significantly affect the dimensional stability of the composite. This result shows that the addition of calcined eggshell particles can improve the material's resistance to engine lubricating oil.