ON MECHANISM OF CONTACT BETWEEN METAL SURFACES .2. REAL AREA AND NUMBER OF CONTACT POINTS

Assuming that the distribution curve obtained from the profile curve of the surface has a normal distribution, the relation between the real contact area and the separation is obtained theoretically in the case of ideal- plastic flow of the microcontacts. If the asperities are cones of the same angle which depends on the surface roughness, the three-dimensional number and the distribution of the radii of contact points are also deduced theoretically. The results of the theoretical analyses are compared with the experimental results for the real contact areas and the numbers of the contact- points. Results show that over the wide load range the average radii of contact points are almost constant; consequently, the total contact area is increased mainly owing to the increase in the number of the contact points. ©1968 by ASME.