Relating Elastic Modulus to Indentation Response Using Atomic Force Microscopy

摘要

In this work, an atomic force microscope (AFM) has been to probe the mechanical properties of polymer samples through examination fo force curves produced during tip-sample contact and indentation. Three types of cantilevel probes with spring constants estimated to be 0.5-0.6 N/m, 2-3 N/m and 40-60 N/m, respectively, were used to study different polymer samples with known modulus values ragning from 0.5 MPa to 3 GPa to 3 GPa. A methodology is developed that (1) related the elastic modulus of the sample to the sample response measured using AFM force curves; and (2) illuminates the importance of the relative stiffnesses of the cantilever probe and the sample to the determination of the elastic modulus.