In order to predict the static friction of grinding surface more accurately

based on fractal geometry theory

Hertz contact theory and tangential contact load theory

the actual contact area

total normal contact load

and total tangential contact load are deduced and the fractal model of static friction coefficient is established accounting for asperity interaction and the domain extension factor. The effects of total normal contact load

fractal dimension

and height scaling parameter as well as material parameters on the static friction coefficient are investigated. Calculation results show that the static friction coefficient increases with the increase of normal contact load. The static friction coefficient decreases as the height scaling parameters or material parameters increase. The static friction coefficient depends sensitively on the fractal dimension and exhibits nonmonotonic characteristics. The static friction coefficient increases with the increasing of fractal dimension as the fractal dimension is less than 2.65; the static friction coefficient increases with the decreasing of fractal dimension as the fractal dimension is more than 2.65. Finally

the effectiveness of the static friction coefficient is compared with the existing model as well as experimental results.