Method for Determining the Coefficient of Friction Variation Pattern as a Function of Density at Low Temperatures Using the Example of Dry Ice–Steel Contact

Abstract

The developments in manufacturing technologies are expected to reduce energy input without compromising product quality. Regarding the material densification process, numerical simulation methods are applied to achieve this goal. In this case, relevant material models are built using functions that describe the variation in mechanical parameters of the material in question due to its deformation. The literature review conducted for this research has revealed a shortage of experimental research methods allowing a determination of the coefficient of friction at low temperatures, approximately 200 K. This article proposes a method for determining the friction coefficient of dry ice sliding against steel. The experimental results were analysed to obtain several functions describing the variation in the coefficient of friction. These functions were then compared using goodness-of-fit indexes. Finally, two functions with similar goodness-of-fit values were chosen. The findings of this research project will complement the already available information and may be used in various research and implementation projects related to the development or improvement of currently used crystallised carbon dioxide conversion processes.

Analysis of Density Distribution in a Cylindrical Specimen under Compaction Using the Example of Dry Ice

“…Additionally, in the literature, the authors made available the results of research work on the numerical models developed, where the nature of the change in the values of the material’s mechanical parameters as a function of density, such as Young’s modulus, Poisson’s ratio or coefficient of friction, was determined. For those interested, we recommend the indicated publications [ 19 , 20 , 21 ].…”

“…Since numerous publications [19][20][21] have demonstrated that the mechanical properties of dry ice change with a change in the degree of compaction, the authors decided to reflect these changes through the use of the VUSDFLD subroutine, which defines yield stress values (Table 1) as the criterion determining the change in material properties. This means that the input values of the parameters describing material properties that Abaqus will take for a given calculation step will depend on the determined PEEQ (equivalent plastic stress) values obtained in the previous calculation The material that is being compacted was modelled as a deformable object and the Drucker-Prager/cap (DPC) model was used to describe its mechanical properties.…”

“… Model used to simulate dry ice compaction in a closed chamber: 1—barrel, 2—ram, 3—extruded dry ice, 4—dead-end disc, 5—force measurement point [ 19 ]. …”