Numerical Investigation of In Situ TEM Tensile Tests  Full text 

F. Nürnberger¹, M. Stolbchenko², O. Grydin¹, G. Gerstein¹, D. Faßmann¹, M. Schaper¹

¹Faculty of Mechanical Engineering, Institute of Materials Science
Leibniz University Hanover, An der Universität 2, 30823 Garbsen, Germany
[email protected]
²National Metallurgical Academy of Ukraine
Gagarina Avenue 4, 49600 Dnipropetrovsk, Ukraine

UDC 620.172:669.14:621.771.23

Metall. Min. Ind.,  2012, Vol. 4, No. 4, pp. 33-40

Abstract

The microstructure and material damage due to elastic-plastic strains can be investigated by means of tensile tests in the transmission electron microscope. Owing to the non-standard specimen geometries which are adapted to the time-consuming preparation methods, it is only possible to make conditional statements about the stresses and strains operating in the region of observation. For this reason, a numerically based method was developed to determine a correlation between the displacement of the specimen’s loading-fixture and the locally operating stresses or strains observed in the material region. Here, the TEM specimen geometry is firstly modelled using FE-software. Following this, a tensile test is numerically simulated for this geometry by means of the FE-software and the corresponding determined stresses or strains are ascertained for the respective displacements. In this way, it is possible to correlate the microstructural changes observed in the transmission electron microscope with the local strains during the in situ tests.

Keywords: IN SITU TENSILE TESTS, TEM, FEM