Fig 5. Young’s modulus on different positions on a thin PAAm sample.

These measurements were carried out at an indentation speed of 1 μm/s using an indenter bead with a diameter of 21.82 μm and a setpoint force of 300 nN. The distributions of Young’s moduli are broad and mean values vary from one position to another. Measurements on different sample positions as well as several measurements at one position are necessary for reliably determining Young’s moduli.