Evaluation of macroscopic stresses in discrete element models of sintering processes

Jerzy Rojek¹ , Szymon Nosewicz¹, Katarzyna Pietrzak^1,2, Marcin Chmielewski²

¹Institute of Fundamental Technological Research (IPPT PAN), Pawińskiego 5B, 02-106 Warszawa, Poland.
²Institute of Electronic Materials Technology, Wólczyńska 133, 01-919 Warszawa, Poland.

DOI:

https://doi.org/10.7494/cmms.2015.1.0526

Abstract:

This paper presents investigation of macroscopic stresses in powder metallurgy process modelled with the discrete element method. The discrete element model belongs to the class of micromechanical models. In the DEM model the material is represented by an assembly of particles interacting by contact forces and the method is formulated in terms of forces and displacements. In order to evaluate macroscopic stresses a special upscaling procedure is necessary. The paper presents basic formulation of the discrete element method with special attention for the contact interaction models for powder compaction and sintering. A method to evaluate macroscopic stresses based on the two level averaging is presented. The discrete element model of sintering is verified using own experimental results. Macroscopic stresses are calculated for the whole process including loading, heating, sintering, cooling and unloading. It has been found out that the macroscopic stresses are consistent with changing process parameters. The procedure is suitable for multiscale modelling of sintering.

Cite as:

Rojek, J., Nosewicz, S., Pietrzak, K., & Chmielewski, M. (2015). Evaluation of macroscopic stresses in discrete element models of sintering processes. Computer Methods in Materials Science, 15(1), 219-225. https://doi.org/10.7494/cmms.2015.1.0526

Article (PDF):

Keywords:

Sintering, Modeling, Discrete element method, Macroscopic stresses

Publication dates:

Received: 27.11.2014, accepted: 17.12.2014, published: 10.01.2015

Publication type:

Original scientific paper

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