Topic: In situ Nano‐ and Micromechanics: Much more than a mechanical microscope 

　　Speaker: Dr. Christoph Kirchlechner

　　　　　　 Department Structure and Nano‐ and Micromechanics (Prof. Dehm) 

　　　　　　 Max‐Planck‐InstitutfürEisenfoschung GmbH, Düsseldorf 

　　Time: 10:00-11:30,Thursday,Nov.8, 2018 

　　Venue: Room 468, Lee Hsun Building, IMR CAS 

　　Welcome to attend! 

　　Abstract： 

　　During the last two decades continuous efforts were made to extract the mechanical properties at themicron and submicron scale [1, 2]. Today, we are well able to experimentally measure the local strengthof single crystals and their size [3] and strain rate dependent behavior [4], the impact of grain - and phaseboundaries on strength, as well as the local fracture toughness of phases and interfaces [5]. Butmicromechanical testing is much more than just being a “mechanical microscope”: Continuous efforts aremade to hook these mechanical tests on dedicated characterization techniques - such as scanning electronmicroscopy (SEM), transmission electron microscopy (TEM) and synchrotron based Laue microdiffraction(μLaue) [6]. 

　　During the talk an overview on nanomechanical testing will be given: As first example, we will show in situSEM to understand the critical resolved shear strength of the {110}, {112} and {113} slip systems in body centered iron. Subsequently, new light on the Hall‐Petch effect and dislocation slip transmission through various grain boundaries based on in situ SEM, TEM and Laue will be given [4, 7 - 9]. 

[1] M.D. Uchic, P.A. Shade, D.M. Dimiduk, Ann. Rev. Mater. Res. 39 (2009) 361‐386. 

[2] G. Dehm, B.N. Jaya, R. Raghavan, C. Kirchlechner, Acta Mater. 142 (2018) 34. 

[3] B. Philippi, C. Kirchlechner, J.S. Micha, G. Dehm, Acta Mater. 115 (2016) 76‐82. 

[4] N.V. Malyar, G. Dehm, C. Kirchlechner, Scripta Mater. 138 (2017) 88‐91. 

[5] R. Soler, S. Gleich, C. Kirchlechner, C. Scheu, J.M. Schneider, G. Dehm, Materials & Design 154 (2018)20‐27. 

[6] C. Kirchlechner, J. Keckes, J.S. Micha, G. Dehm, Adv. Eng. Mater. 13(8) (2011) 837‐844. 

[7] N.V. Malyar, J.S. Micha, G. Dehm, C. Kirchlechner, Acta Mater. 129 (2017) 91‐97. 

[8] N.V. Malyar, J.S. Micha, G. Dehm, C. Kirchlechner, Acta Mater. 129 (2017) 312‐320. 

[9] N.V. Malyar, B. Grabowski, G. Dehm, C. Kirchlechner, Acta Mater. (2018).