Abstract: The wear of gears is studied with high load at low speed ( υ == 1～4m/ s ). The research results show that these gears work in the states of boundary lubrication and that the wear phenomenon is related to the local eddy in the boundary film of the lubricant. It is also found that there is a velocity which is the worst one and at which the maximum wear rate of gear will occur. The value of this velocity is related closely to the operating conditions of the gear and is found to be 1.13～1.41m/ s in the tests.

Key words: Gear, Wear, Worst velocity