GranuHeap instrument as new tool for a fast and easy determination of the flow ability and the cohesion of a granular material
GranuHeaP is the first entirely automated instrument able to measure quickly and with high degree of accuracy the repose angle of granular or pulverulent material. Thanks to a simple algorithm, GranuHeap also measures a cohesive index that provides information on the flow properties of the studied powder. Results are shown for clay, flour, lactose, polymeric and metallic powders.
GranuHeap instrument is used to estimate the cohesion of several metal powders. The results are used to correlate the flow properties to the grain size distribution and the shape of the metal powders. For this, the shape of the true powder heap with the shape of a heap presumably ideal and free from cohesion are compared. The obtained cohesive index authorizes a simple and fast comparison on various samples.
Milling effect on the flow ability of a superconductor powder (Granupack by Granutools and GranuDruM analyses)
For most practical superconductor applications, a high current density (Jc) is required. This may be guaranteed by controlling the shape-forming processing strategies. As the commercial powder contains large agglomerates, these lasts have been broken before performing the shape forming steps. In this application note, we study the effect of the milling process on the flow ability properties of YBa2Cu3O7−x ceramic.
Measurement of flow ability and cohesion in metal powders using GranuDruM instrument (GranuDruM analyses)
GranuDruM instrument is used to measure the flow ability and the cohesion of metal powders by comparing the wave of powder under motion in a rotating drum. The results give information about the adherence (static part of the flow) and the shear/friction part of the flow.
To guarantee a high reproducibility of processes, a lot of applications need the use of free flowing powders. For plasma spraying deposition, for example, the substrate needs to receive a regular and constant flow mass of powder during all the projection duration in order to ensure the regularity of the coating thickness during all the process. The rheological properties of the powders are analysed before and after the spray-drying process.
GranuDruM instrument has been developed to measure the dynamic flow properties of a powder for different rotating speed. Therefore, the flow abilities of the powder measured as a function of the shearing rates of the cell (rotating speed) allows to evaluating rheological properties such as shear thinning or shear thickening. In addition, GranuDruM is able to give information about the flow robustness of the powder and its ability for natural granulation.