Boundary lubrication effect of organic residue left on surface after evaporation of organic cleaning solvent

Abstract

Although samples are visibly clean, organic deposits could have tremendous impacts on tribological measurements and interpretation of friction and wear behaviors. This paper discusses the boundary lubrication effects of invisible residues from organic solvents that have been widely used in tribological studies in ambient conditions. Stainless steel, soda lime glass, and copper substrates were cleaned using UV/ozone treatment or organic solvents such as alcohols where the solvent was allowed to evaporate from the surface. In ball-on-flat tribo-tests, all UV/ozone cleaned samples showed high friction and catastrophic wear immediately upon sliding due to the absence of lubricants at the sliding interface, while samples cleaned by organic solvent experienced low friction and minimal wear for hundreds of reciprocating cycles. Analyses of the surface by atomic force microscopy and vibrational spectroscopy indicated that the solvent cleaning deposits hydrocarbon residue on metal and oxide substrates. This residue is due to trace impurities with low vapor pressures inevitably present in the bulk liquid, regardless of solvent

Effects of tempering and heat strengthening on hardness, indentation fracture resistance, and wear of soda lime float glass

“…They were then cleaned by rinsing with deionized water, ethanol, and then again with deionized water and blown dry using clean nitrogen. Samples were then UV‐ozone cleaned to remove organic contaminants before testing …”

Differences in surface failure modes of soda lime silica glass under normal indentation versus tangential shear: A comparative study on Na+/K+‐ion exchange effects

“…Ten gram of KNO 3 (>99.0% from Sigma Aldrich, Burlington, MA, USA) was pre‐melted at 400°C in the SS bath and kept covered. Prior to ion‐exchange, the SLS samples were cleaned by rinsing with DI water and pure ethanol, then UV‐ozone exposure for 20 minutes . The glass samples were preheated to 400°C in the same oven and then immersed into the molten KNO 3 bath.…”

Chemical structure and mechanical properties of soda lime silica glass surfaces treated by thermal poling in inert and reactive ambient gases

“…The samples were cut into roughly 3 cm × 3 cm size and cleaned by first rinsing with ethanol and DI water, and then by UV‐ozone to remove organic contaminants on the glass surface before thermal poling. The poled samples were cleaned once again before surface characterization …”

“…The poled samples were cleaned once again before surface characterization. 22 A schematic diagram of the thermal poling setup with environmental control is shown in Figure 1. Stainless steel plates were used for both anode and cathode.…”