Derjaguin-Muller-Toporov (DMT) model of elastic contact between two spheres (contact radius)

Description

Contact mechanics is the study of the deformation of solids that touch each other at one or more points. The Derjaguin-Muller-Toporov (DMT) model is an alternative model for adhesive contact which assumes that the contact profile remains the same as in Hertzian contact but with additional attractive interactions outside the area of contact.

Related formulas

Variables

aThe contact radius (m)
RRadius R = (R1*R2)/(R1+R2) (m)
EYoung's modulus of the two spheres (Pa)
FForce applied on the body (N)
γHalf of the total surface energy of both surfaces per unit area (J/m2)
πpi