Powder Rheometer - A Device to Know the Parameters of Powder Materials

To study the nature of matter that is in powder form is a complex task as the material shows significant transformations. A powder is something that can behave either like liquid or like a solid, all depending upon the pressure applied. Generally, there are three powder flow properties that are taken into consideration-

1. Dynamic State
2. Static State
3. Quasi-static state

There is a need to study the flow of powder to analyze its properties. For powder flow measurement we use different techniques. Powder’s rheology can be easily studied with the help of a powder rheometer. There are many situations in which there comes a need to measure and analyze the properties of powder for example, in the case of salt, flour, sugar or anything in granulated form. To study the different parameters of powders, these are ideal as they show the influence such as size, distribution, and shape.

There is another property of powder according to which the powder decreases its initial volume when pressure is applied to it. The term used for that is “Powder compressibility”. There is also compactibility. Compactibility means the ability of powder to get compressed in such a way that it becomes a tablet with a specific radial tensile strength. This strength is generally judged on the basis of hardness caused by deformity due to compression.

Powder Rheometer

Powder rheometer is a device or instrument that is specially modeled to study the rheology of powder or in easy words; it is designed to characterize the powder flow properties. A powder rheometer not only characterizes the properties but also works as a powder flow tester. It processes when the powder is in motion, this way the resistance of the powder to flow measurement takes place. A massive range of powder testing methods is provided by the powder rheometer.

Generally, the methods used are shear test, wall friction test, permeability test, compressibility test.

When we talk about shear test, the work of shear test is to measure the amount of shear stress due to relative movement of powder particles when normal stress is applied through them. This stress is purely based on 5 different levels to obtain a specific data to analyze the property of powder.

Wall friction test, on the other hand, quantifies the required work done to move bulk particles right across the surface of a certain wall. The measurement in this one takes place in the same way as that of the shear test. The other two tests are also the same but the difference is that in one test we apply a certain amount of air velocity under same situations and the other one is used to test the compressibility by the different method.

But the main motive of powder rheometer is too deeply analyze the properties of the powder and study the powder flow measurements.