| Topic Master Thesis | Department MSK |
Background
Traditionally, nanoindenters were designed to measure hardness and modulus of materials at the micron to sub-micron scale. These devices employ high-resolution instrumentation that allow for the continuous measurement of force and displacement. These force-displacement curves are usually rich in information; they reveal a variety of mechanical properties and the underlying deformation mechanisms.
Such measurements are predominantly done under compression conditions. Nanoindenter-based uniaxial tension tests are currently restricted to in situ settings within SEM or TEM environments. These in situ tests pose significant challenges, compounded by the significantly lower load capabilities. Consequently, only very small volumes can be conveniently tested. Extending this capability to ex-situ conditions would streamline the test process and increase the range of sample sizes that can be tested. Hence, a device converting the compressive load of the indenter to a tensile load applied to a sample is required.
Objective
1) Designing a reverse-action device (RevAD) that allows for the translation of compressive forces to tensile forces in a nanoindenter using CAD software
2) Prediction of the stress-strain behaviour as a function of the applied indenter load using finite element analyses
3) Parametric study of the device's adjustable stiffness; sensitivity analysis
4) Case study: simulating tensile loading of a magnesium single crystal
Your Qualification knowledge of technical mechanics and the Finite Element Method
Duration 6 months
Start ASAP
Contact Henry Ovri (henry.ovri@hereon.de); Dirk Steglich (dirk.steglich@hereon.de)
Background
www.hereon.de/institutes/material_systems_modeling/projects/index.php.de