Application of Mathematical and Experimental Approach in Description of Sedimentation of Powder Fillers in Epoxy Resin

Abstract

In this paper, sedimentation inhibition attempts were examined using colloidal silica in a mathematical and experimental approach. Experimental results were validated by a two-step verification process. It was demonstrated that application of quantitative metallography and hardness measurements in three different regions of samples allows us to describe the sedimentation process using modified Stokes law. Moreover, proper application of Stokes law allows one to determine the optimal colloidal silica amount, considering characteristics of applied filler (alumina or graphite). The results of mathematical calculations have been confirmed experimentally—the experimental results show good agreement with the calculated data.

The Influence of Graphite Filler on the Self-Lubricating Properties of Epoxy Composites

“…The tests assumed that the optimal measurement time is 5 min after adding the hardener and graphite. A more detailed physical and mathematical description of the phenomena and sedimentation parameters were described in a previous publication [ 47 ]. The test results are presented in Figure 5 .…”

“…The production of thermoset polymer composites where short fibers or granular fillers are the dispersed phase is difficult due to a number of phenomena leading to the occurrence of various problems. The most common problems in liquid resin systems include the following [ 46 , 47 ]: Sedimentation of filler particles; Porosity of the material; Filler particles flotation; Inhomogeneity caused by [ 47 ] agglomeration of filler particles; High crosslinking temperature leading to resin boiling in the volume; Limited production time due to crosslinking reactions. …”

“…The production of thermoset polymer composites where short fibers or granular fillers are the dispersed phase is difficult due to a number of phenomena leading to the occurrence of various problems. The most common problems in liquid resin systems include the following [46,47] • Limited production time due to crosslinking reactions.…”

Study on non‐uniformity and dynamic fracture characteristics of GIL tri‐post insulators considering Al2O3 sedimentation

“…And Al 2 O 3 particles are initially stationary, so when t = 0, v P = 0. It can be concluded that the settling velocity of Al 2 O 3 particles is [23,24]:…”

“…And Al 2 O 3 particles are initially stationary, so when t = 0, v P = 0. It can be concluded that the settling velocity of Al 2 O 3 particles is [23, 24]: $$${v}_{\mathrm{P}}=\frac{{d}_{\text{P}}^{2}g}{18\mu }({\rho }_{\mathrm{P}}-{\rho }_{\mathrm{L}})$$$ …”