Issue |
EPJ Web Conf.
Volume 183, 2018
DYMAT 2018 - 12th International Conference on the Mechanical and Physical Behaviour of Materials under Dynamic Loading
|
|
---|---|---|
Article Number | 01061 | |
Number of page(s) | 6 | |
Section | Modelling and Numerical Simulation | |
DOI | https://doi.org/10.1051/epjconf/201818301061 | |
Published online | 07 September 2018 |
https://doi.org/10.1051/epjconf/201818301061
Design and Optimization of Dynamic Test Samples for Ductile Damage Assessment
1
Department of Industrial Engineering and Methematical Sciences, Università Politecnica delle Marche,
Ancona - Italy
2
Università degli Studi eCampus,
Novedrate - Italy
3
Department of Mechanical and Aerospace Engineering, Sapienza University of Rome - Italy
4
Faculty of Science and Technology, Free University of Bozen-Bolzano - Italy
* Corresponding author : m.sasso@univpm.it
Published online: 7 September 2018
The present research aims at assessing and comparing the damage evolution in a structural steel, mainly used in pipeline applications, both under quasi-static and dynamic conditions. Accordingly to the core of the literature related to plastic damage modelling, two key parameters must be controlled in the tests: the stress triaxiality and the Lode angle, both depending on the stress state. Either strongly affect the material strain to failure. Hence, different specimen geometries are needed to test the material in the desired ranges of these parameters. In this work, three kinds of geometries typically used in static tests, i.e. round and notched cylindrical, and thin rectangular, have been considered and adapted to an available Hopkinson bar facility. The shape of the specimens (diameter, fillet/notch radius, thickness, gauge length) and the incident pulse intensity have been studied within a multi-objective optimization scheme, in order to achieve similar strain rates for the three kinds of tests, with nearly constant time histories of strain rate, triaxiality and Lode angle during deformation. More specifically, the adopted solutions permitted to achieve an average strain rate of 3500 s-1, with varying triaxialities from 0.5 to 1.2, Lode angles from 0.5 to 1 and strains to failure from 0.8 to 1.5.
© The Authors, published by EDP Sciences, 2018
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.