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Researchers applied a formulation which includes both elastic adhesion and sintering to the study of coalescence of a Maxwell viscoelastic sphere to a rigid flat surface. The initial coalescence is due to elastic adhesion then a zipping mechanism causes a transition to viscous sintering. This zipping mechanism is due to attractive forces outside the area of contact. The next stage in the process is a stretching mode of coalescence which is due to curvature-based tractions. The contact radius at which the transition from zipping to stretching modes occurs is related to the sphere radius.

A new parametric tip force-distance relation (PT/FDR) is shown for describing the probe-sample system in atomic force microscopy (AFM). A surface integration technique is designed to calculate the interactions between arbitrarily shaped bodies. The technique is based on the Hamaker pairwise in integration in a continuous fashion, reducing the six-dimensional integration to a four-dimensional procedure. The PT/FDR is derived and a nonlinear fitting process is utilized to extract the model parameters and the Hamaker constant from AFM force-distance data.