Abstract: According to the original proposal of Bowden and Tabor and based on the fractal theory,the total adhesive friction coefficient is expressed as a combination of the adhesive friction coefficient in elastic and plastic regime.Then a fractal model of adhesive friction coefficient is proposed.And a mathematical model of the relationship of powder particles' internal friction and fractal parameter is built.Through the function curves,it is analyzed that the fractal dimension of the surface of the powder particle has impact on the total adhesive friction coefficient and the inner friction.The study shows that for certain fractal dimension,the total adhesive friction coefficient reduces sharply as the normalized contact area increases and the inner friction can reach the value of plastic shearing intensity rapidly as the fractal dimension and the temperature of the surface of the powder particle increase.

Key words: fractal dimension, HVC, adhesive friction coefficient, internal friction