Derjaguin-Muller-Toporov Contact Mechanics
Adhesive contact: DMT vs JKR model comparison and force-displacement curves
Material Parameters
Tip radius R (nm)
20 nm
Eff. modulus E* (GPa)
10 GPa
Work of adhesion W (mJ/m²)
50 mJ/m²
Model
Both
DMT only
JKR only
Hertz only
DMT:
F = 4/3 E* √R δ^(3/2) - 2πWR
JKR:
includes contact radius (soft/adhesive)
Tabor parameter μ:
—
μ<0.1: DMT regime
μ>5: JKR regime
Pull-off force:
DMT:
—
JKR:
—
Contact Geometry
Force-Displacement Curve F(δ)