Measurement of Darcian Permeability of foundry sand mixtures

Gas permeability of moulds and cores is an important factor to consider in the casting process. In foundries, gas permeability is measured by using instruments which give dimensionless numbers. This approach enables the comparison of values between samples and is often not quantified in units. In this study, a custom-made measurement system is introduced that applies Darcy's law, where pressure gradients for different flow rates are studied. The Darcian permeability in standard cylindrical samples was determined using a method that is familiar with those in earth sciences. Two types, steady-state and unsteady-state approaches were used for the calculations, and the difference in permeability values generated by these two methods is discussed. The results of a silica sand sample with furan resin and a 3D-printed sample that consists of artificial granulous material with phenolic resin were compared.

Automated summary

Gas permeability of moulds and cores is crucial in the casting process. This study introduces a custom-made measurement system and compares results using different calculation methods.