Minimum Quantity Lubrication in Cold Work Drawing Process: Effects on Forming Load and Surface Roughness

AbstractIn this study, experimental analysis has been employed to evaluate the effects of minimum quantity lubrication on the deformation of aluminium workpiece over a tool. The effects of lubricant on forming loads and surface finish were evaluated under dry and lubricated conditions between die-workpiece sliding surfaces. Palm olein (PO) with dynamic viscosity of 38.9 mPa.s at 40°C in 1, 5, 10, and 20mg amounts were used as test lubricant. A constant forming speed of 10mm/s on the workpiece was used as inputs for the experimental analysis. The load-displacement behaviour was observed during the steady- state condition. It was shown that significant differences exist between lubricant quantity, load-displacement distribution and surface finish of the product

Properties of Palm Pressed Fibre for Metal Forming Lubricant Applications

AbstractDuring the last few years, special attention has been paid to the protection of the environment from pollution caused by lubricants. Green lubricants are in demand for many industrial activities. Present work focuses on palm pressed fibre (PPF), which is the biomass waste generated during the production of palm oil. It has a great potential source of lubricant by producing the PPF oil by pyrolysis. As the availability of PPF is abundant and the PPF waste generates greenhouse gases, the present investigation aims at pyrolysis experiments and evaluating the yield and functional properties of the oil produced. Experimental studies on catalytic pyrolysis technology using a tubular reactor on PPF oil was performed at temperature of 450°C, which gave oil product yields of 44.1 percent. Viscosity of the PPF oil as a function of temperature was measured at different temperatures ranging from 25°C to 50°C. The result showed that the viscosity of the oils decreases remarkably with increases in temperature. Finally, the PPF oil obtained from the pyrolysis process was tested as a lubricant and compared with palm olein (PO) in cold work drawing process. The findings revealed that PPF can perform as effectively as existing lubricants like PO in metal forming process

The wettability characteristics of DLC coating for tribological engineering applications

Hard coating deposited to tool steel surface can greatly improve wear resistance and reduce sticking. Since solid-liquid interactions are present in every lubricated tribological contact, the present study is aimed to understand the physical phenomena of contact interactions between the DLC coated surface and the liquid. In this study, double-layer DLC/TiAlN coating was prepared via Physical Vapour Deposition (PVD) process. The anti-sticking properties were assessed using contact angle measurements using two liquids with distinctly different viscosity – water and oil. No significant differences found in the contact angle values for both liquid properties. The results revealed that the DLC/TiAlN coated tool steel surfaces exhibit hydrophobic behaviour with high contact angle values. With a lower surface energy of the DLC/TiAlN coating in comparison to uncoated surface, this suggests that the DLC/TiAlN coating is a good hard coating candidate since it has a lower adhesion resistance and an improved release performance

Manufacturing strategies and tribology of tailored tool surface topographies for enhanced lubrication in metal forming

Lubricants are applied extensively in metal forming. Currently, methods to prevent wear are always emphasize the need for lubricants with ability to form boundary layers, chemically bonded to tool and workpiece surfaces. Tailored tool surface topography, as a kind of new engineered tool surfaces consisting of lubricant pockets on a hard tool material, has attracted great attention from investigators in facilitating micro-hydrodynamic lubrication impeding wear on tool surface by less harmful lubricants in metal forming. In the present paper, overview of manufacturing strategies of tailored surface topographies on hard tool material reported by different investigators are explained. Recent development and challenges on adopting strategic tool surface topography as one of environmental friendly alternatives for enhanced lubrication in metal forming and their suggested amount of real contact area α influencing friction are discussed