Powder filling
Powder pressing is often a complicated process as the behaviour of the powder material changes with increasing density. Manufactures tend to produce components with more complicated shapes which demand complex pressing equipment and methods. This implies a better knowledge of the material response during the pressing process. Mechanical properties of powder materials changes dramatically from the beginning to the end of the compaction phase. Previous investigations have shown that powder transfer and high powder flow during filling affects the strength of the final component significantly.
In this work an experimental setup will be established by SECO Tools to be used for study the powder behaviour and for the characterisation of the die filling as part of the process in powder pressing. Building powder measurements equipment jointly with advanced dynamic measurements using digital speckle photography (DSP) of powder filling is likely to improve the knowledge of a critical part of the process. Measurements will also support development of numerical models. Experimental studies combined with simulations is then likely to improve the understanding of the filling stage, e.g. to explain the non-homogeneity of the density of powder pressed parts.
In the project, studies of different numerical methods as discrete element method (DEM) and smoothed particle hydrodynamics (SPH) method will be in focus. The methods are used to study powder flow behaviour and velocity fields.
The project is founded by Seco Tools and Sandvik
Project leader: Pär Jonsén
Researchers: Gustaf Gustafsson , Pär Jonsén and Hans - Åke Häggblad