Wear properties of new porous carbon materials: Woodceramics

The purpose of this investigation was to analyze the fundamental wear properties of new porous carbon materials "Woodceramics". Wear tests were carried out by sliding an alumina ball (R=1.5, 4.0 mm) or hemispherical diamond pin (R=0.075 mm) against a Woodceramics plate (MDF-800), under three lubrication conditions: unlubricated in air, impregnated with base oil, and in water. The specific wear rate was calculated from the profile of the worn surfaces, and the relationship between the specific wear rate and the contact pressure parameter (W/R²)^1/3 was obtained. Worn surfaces were observed with a scanning electron microscope (SEM) to clarify the microscopic wear mechanisms. The following principal results were obtained: (1) The specific wear rate of Woodceramics increases rapidly with increasing contact pressure parameter (W/R²)^1/3, under all lubricated conditions; (2) When the contact pressure parameter (W/R²)^1/3 is less than a certain critical value, the specific wear rate of Woodceramics is less than 10^-8 [mm²/N], which is low enough for practical use; (3) The wear mode of Woodceramics can be classified into the following three modes: large-scale brittle fracture-induced wear (flake formation), small-scale brittle fracture-induced wear (powder formation), and ultra mild wear (ploughing).