Abstract: The lubrication of spheroidal graphites and the smaller stress concentration coefficient are generally considered to be the causes of good wear resistance of ductile iron. Through TEM observation, however, the writers yet discover that there innately exists higher density of dislocations in the matrix of ductile iron, and a much denser dislocation band is also observed in tire neighbourhood of the spheroidal graphite. Experiment shows that the denser the dislocations in the matrix, the better the wear resistance of ductile iron. Thus it is convinced that the fact of dislocations existing in the matrix is just the mechanism of wear resistance of ductile iron.

Key words: 耐磨性, 位错密度, 铸型刚度, dynamic characteristics, flexible hinge, gas squeeze film, Near Field ultrasonic levitation