Powder Rheology with Anton Paar Rheometers

Anton Paar’s new Powder Cell has been designed to turn every rheometer from the renowned MCR series into a powder rheometer and in this way brings the full array of traditional rheological methods to the field of powder. Now it is possible to simulate and determine powder flow under different conditions. This is important in the field of quality control, but also to investigate dry granular flow, especially in the fluidized or near-fluidized state. An MCR powder rheometer is the perfect setup for true rheological investigations of powders in quality control as well as research and development.

Working with powders creates challenges, particularly when it comes to processing and storage and also intake and predelivery control. Most of these challenges are related to powder flow. Powder flow is influenced by a wide range of factors such as particle size and shape, chemical structure, humidity, temperature, packaging behavior, static charge, surface morphology, etc. An MCR powder rheometer can simulate and determine powder flow under different conditions and therefore ensures efficient quality control and smooth powder processing.

Powders – as a mixture of solids, liquids and gases – are complex. This complexity can be simplified with one value: Cohesion Strength. Cohesion Strength is the internal resistance of the powder to flow. Based on Cohesion Strength it is possible to predict whether the powder will flow through a process smoothly and whether the quality of a powder has changed. The bottom line is that no matter which factor influences a powder, the established Cohesion Strength value will change. This value can easily and exactly be determined with an MCR powder rheometer.

The powder rheometer from Anton Paar delivers reliable and reproducible results by clearing the “powder memory” with fluidization. Furthermore an automatic measurement program ensures results within two minutes and therefore high throughput. The Powder Cell is easy to use. It provides automatically performed calibration and live visualization of the measurements. Operating costs are low and the unique dust protection hood safeguards the operator and the instrument from fine and potentially hazardous powder.

More than just an instrument for quality control, the Powder Cell for the MCR rheometer series is also a unique instrument for the study of dry granular flows, especially in the fluidized or near-fluidized state. It brings the amazing precision achieved with MCR rheometers from Anton Paar to the field of granular media. It not only includes a high-precision pressure-drop device but also enables rotational as well as oscillatory tests in any state of consolidation or fluidization and any state in between. A further benefit includes the precision Mass Flow Controller, which gathers new data between zero-load and the fluidized state.