Polymers are known to exhibit various flow instabilities during extrusion in which a molten polymer is forced to flow through a narrow die, in order to form a strand or acquire a desired shape of the final product. Recent developments in experimental techniques revealed that some of the instabilities are interfacial in nature, that is originate from the violation of the no-slip boundary conditi...

Mechanical wear accounts for one third of present global energy consumption. However, it still lacks an efficient lubricant to simultaneously achieve a highly efficient lubrication and metal wear repair. Herein, we report that carbon quantum dots (CQDs)/CuSx nanocomposites show enhanced lubrication and metal wear surface repair abilities when used as additives. The highly efficient lubrication ...

We consider some basic principles of fluid-induced lubrication at soft interfaces. In particular, we quantify how a soft substrate changes the geometry of and the forces between surfaces sliding past each other. By considering the model problem of a symmetric nonconforming contact moving tangentially to a thin elastic layer, we determine the normal force in the small and large deflection limit,...

Anti friction bearings in process pumps, by design, frequently utilize oil sump lubrication technology. For many years, it was an accepted condition that the lubricating oil used in oil sump bearing lubrication needed to be changed on a regular basis to prevent high levels of contamination that can lead to premature bearing failure, contributing to equipment downtime. Often, the indicators used...

The relationship between a Lubrication Mode Diagram (LMD) for concentrated contacts (LCC‘s) and the ‘IRG transition’ diaLubrication Modes and the IRG Transition D i ag ram gram has been studied. In addition, scuffing results, obtained by the IRG (International Research Group) have been analysed, as well as the results of scuffing tests performed by different workers using a two-disc apparatus. ...

Mice lacking Muc2 had an increased ratio of proliferating to apoptotic epithelial cells, resulting in altered maturation and increased migration of epithelial cells in the intestine. They were also more likely to develop intestinal, colon, and rectal tumors. The mice are the first good model for studying rectal tumors, which are common in humans. Anticancer lubrication new mouse model for the s...

The sharkskin surface instability is commonly observed in the extrusion of polymer melts. We present a series of experiments in which a specifically designed rectangular slit die with insulated and independently heated sides and is used to induce precise temperature gradients across a flowing polyethylene melt. Our previous experiments demonstrated that the character of the surface distortions ...

In this study, experimental and numerical investigations were carried out to achieve a comprehensive understanding of the impact surface conditions on self-piercing riveting (SPR) joint quality. Oil lubrication sandpaper grinding employed in tests change at rivet/top sheet, top/bottom sheets bottom sheet/die interfaces. A finite element (FE) model for SPR process was also adopted numerically as...