Dry friction meets mixed/boundary lubrication

The progress in metallurgy and lubrication concepts especially in the last years have built the base to substitute the mixed and boundary lubrication by dry lubrication or solid state friction. Most of the identified material couples exhibits in a wide range of operating conditions only wear rate around 10-7 mm3/Nm. This level of wear rate would allready allow to avoid EP/ AW-additives in oils. Only a few material couples are known today, which combine under dry friction a wear rate of 10-8 mm3/Nm and lower with a coefficient of friction in the milli-range. Unfortunately, these couples work not in air, but in UHV or nitrogen. The first couples with the previous mentioned performance in air up to 450 °C und 6 m/s are antimony impregnated carbon sliding dry against MgO-ZrO2 or Al2O3, which will bost the worldwide efforts in identifying more such couples.