(84f) Powder Characterization at the Edge of Sintering – High- and Low-Temperature Ring Shear Testing

ABSTRACT While the behaviour and mechanical coefficients of solids under the influence of temperature is well understood, how this translates to their behaviour when in the form of particulates is not studied in great depth.[1]

In this Study, we will show both cryogenic as well as high-temperature measurements exploring the different ways that temperature influences the behaviour of bulk solids using dedicated measurement equipment.

From the onset of melt behaviour in partially crystalline polymers like Polyamide to the effect of the freezing of surface water in flour and other biological samples, the embrittlement of resins at low temperatures to the effect of drawing surface water from the atmosphere in cement.

Special consideration will be given to the functional mechanisms that are occurring at the edge of sintering temperature and the normal-stress dependent evolution of powders in or near a sintering regime.

All of these effects have their distinct signatures upon the flow behaviour and of course, play a major role in their caking behaviour. Both the data, their influence upon silo and hopper design as well as interpretations of the underlying mechanisms will be shown.

REFERENCES

[1] Tomasetta, Igino, Diego Barletta, and Massimo Poletto. "Correlation of powder flow properties to interparticle interactions at ambient and high temperatures." Particuology 12 (2014): 90-99.