Papers by Keyword: Lubricant

Abstract: Lubricants are substances that minimize wear and friction for optimal performance and lower the likelihood of malfunctions. Over 95% of lubricants used today are made of non-renewable petroleum, which is being depleted and emitting emissions that are bad for the environment and people's health. The greatest substitutes are biolubricants, whose primary sources include edible and inedible oils that are generated from lipids and carbohydrates found in various animals, plants, and microbe sources, with the exception of Algae. An eco-friendly and sustainable resource for green lubricants, microalgae oil is vital to the lubricant business. Microalgae are photoautotrophs, meaning they grow quickly and can be grown multiple times a year with less energy needed. Because microalgae do not require agricultural land or climatic conditions to develop, they may also be produced in wastewater and saltwater. As a result, their production costs are also lower. Microalgae has exceptional chemical compositions, including significant levels of lipids, hydrocarbons, polysaccharides, and gelling properties. Microalgae are suitable for lubrication because they contain high amounts of saturated, mono-unsaturated, and polyunsaturated fatty acids, which give algae their good tribological, physiochemical, and rheological qualities and minimize friction. Molecular weight, viscosity, oxidation stability, thickening behaviors, friction coefficient, antiwear, antiseizure, thermal stability & characteristics, crystallinity, and rheology of polysaccharides as sustainable green lubricant are all covered in this review study about the lubricating properties of microalgae oil.

Abstract: Carbon nanomaterials have piqued the interest of researchers over the last two decades due to their proven wear and friction properties, in addition to tribological application. This review provides a detailed analysis of the latest discoveries in tribology of four common carbon nanoparticles are carbon nanotubes (CNTs), graphene, nanodiamonds and fullerene. First, the four forms of carbon nanomaterials are described in terms of their applicability in coating for friction and anti-wears. Second, the use of graphene and CNTs as additions to improve tribological behaviours in bulk materials is discussed. Finally, the mechanisms of CNTs, fullerene, fullerene, nanodiamond and graphene, working as additive to lubricate to reduce wear and friction are discussed. Fourth, the advancements in super-lubricity employing carbon nanotubes and graphene are emphasised. Finally, this study finishes with a look ahead at future research on carbon nanoparticles in tribology, their major barriers for practical use, and prospective remedies.

Abstract: Lightweight construction and performance requirements in the automotive industry have resulted in increased power density. At the same time, this increases the load on the workpieces. To counteract the resulting wear, either a more wear-resistant material may be applied or the functional surface may be specifically modified against wear. Machine hammer peening (MHP) is a process for such a targeted adjustment of the functional surface and the surface area properties. MHP is a mechanical surface treatment, which increases the wear resistance of the workpieces by introducing residual compressive stresses and work hardening as well as by smoothing or structuring the surface. To ensure an accurate adjustment of the surface properties, the influencing factors (material, process parameters and lubricant) and their interactions must be sufficiently well studied and understood. In particular, the influence of the lubricant on the surface area properties has not yet been adequately investigated. The objective of the work presented in this paper was to provide a deeper insight into the influence of the type of lubricant on the resulting surface properties in terms of roughness, residual stresses and hardness. The lubricant’s influence was investigated using a partial factorial experimental design. Additional factors investigated, besides the choice of lubricant, were stroke, distance of indentation and step over distance. The results show a strong influence of the lubricant selection, especially on the resulting surface roughness. For the same process parameters, a deviation of 540 % in the resulting surface roughness was measured between two surfaces machined with different lubricants.

Abstract: This research aimed to reduce die and punch wear and improved the quality of the production process with the application of the Lean Six Sigma methodology. Die and punch had limited capability in cutting material edges in the case study company. The root-cause analysis showed a correlation between the hard coating and the lubricant effect on wear reduction using the design of experiments and DMAIC based on the Six Sigma approach. The results indicated that a combination of AICrN-PVD coating and aloe vera oil provided the most outstanding results in terms of wear reduction. Moreover, it had the potential to minimize the cost of product defects or repairs significantly. These findings showed the effect of the Lean Six-Sigma approach at the die production process, which increased operational efficiency and consistency to enhance business performance and meet customer requirements.

Abstract: The classical tribological systems which are used in cold forming are still based on zinc phosphate as a separation layer and soap as a lubricant. Due to the globalization more and more processes are required following a globalized environmental protection and chemical registration concept. Therefore, the search for resource-efficient and environmentally friendly pretreatment concepts in cold forming are essential to fulfill these demands. One possible solution can be found in the phosphate free cold forming processes. Globally seen, there are different development routes to gain phosphate free tribological systems. On one hand, lubricants have been developed which are working without a conversion layer but leading to less forming performance which is often unacceptable out of profitability. On the other hand, there is the possibility to use a zinc phosphate free conversion coating layer to realize a phosphate free tribological system, without leaving the common system consisting out of a separation layer with a lubricant on top through remaining the same performance known from common systems. Beside this, it is discussed how a further development concept of this system leads to easier and shorter processes introducing a reactive lubricant concept. With the help of the reactive lubricant it is possible to apply a separation layer and a lubricant in one treatment step and obtain a phosphate free separation layer with a self-assembled lubricant on top. This system enables to realize a phosphate-free cold-forming process without changing the application of the lubricant and the forming process.

Abstract: To improve the quality of human life, sometimes, surgical interventions are required to replace or retain damaged tissue during reparative regeneration. Titanium and titanium alloys are well-proven biocompatible materials. The methods of modeling the phase composition of the titanium alloy can be used to predict the chemical and physical-mechanical properties of implants and suture material. In this research, the features of the titanium drawing process are investigated, recommendations are given for thermo-mechanical processing and the choice of a lubricant. Modeling the structure and phase composition of alloys allows predicting their properties and choosing the optimal technological parameters for all drawing transitions. Drawing must be performed in a friction mode close to the hydrodynamic regime with intermediate annealing to control the phase composition of titanium, restore the plasticity resource, and heal crystal structure defects. The composition of atmospheric gases during annealing makes it possible to control the phase composition and properties of the alloy. The use of exfoliated graphite is proposed as a lubricant applied to the anodized titanium surface.

Abstract: The present study describes the impact of cutting speed and various lubricant-cooling process agents on the temperature of alloy turning. The research was conducted for NiCr20TiAl and N07750 nickel alloys with the help of HG30 and HS123 carbide-tipped cutting tools. New lubricant-cooling process agents with nanodispersed diamond graphite additives are studied. The optimal composition of the diamond graphite additives is revealed when cutting these alloys. It is demonstrated on the basis of tests the positive effect of diamond graphite agents on the quantitative changes in measured cutting temperatures. In doing so, the cutting speed and the lubricant-cooling agents applied to the cutting zone have little impact on the nature of temperature patterns.

Abstract: The authors deal with the task of technological maintenance of operability and reliability of packaging equipment at life cycle stages, including its designing, manufacturing and operation. To improve the wear resistance of the most loaded mobile nodes of the lever-hinged gripping device of a packaging machine, a new composite material with upgraded technological and operational characteristics has been obtained, on the basis of studying the physical model of boundary friction. The paper presents the results of investigations of the plasma coating from the developed material.

Abstract: Lubricants and O-rings are necessarily used for the construction of many accelerator-driven facilities as spallation sources or facilities for the production of radioactive isotopes. During operation, such component will absorb high doses of mixed neutron and gamma radiation, that can degrade their mechanical and structural properties. Experimental radiation damage tests of these components are mandatory for the construction of the facility. Methodologies for irradiation in nuclear reactor mixed fields and post-irradiation examination of lubricating oils, greases and O-rings were developed and are here presented. Samples were characterized with standard mechanical and physical-chemical tests. Parametric studies on the dose rate effects have been performed on O-rings. A case studies for a specific O-ring application in a gate valve has been developed. Some of the tested samples showed a dramatic change of their properties with dose, while others remain stable. Results were collected on nine commercial greases, on one oil and on four commercial elastomeric O-rings. The most radiation resistant among the selected products are now considered for application in facilities under construction. The main mechanisms of neutron and gamma radiation damage on these polymers were investigated at the mechanical and structural level.

Abstract: Lubricants have a very crucial role in machinery industry for friction reduction and wear reduction between two relatively moving parts. The current study enlightens the works from various authors on evaluating the tribological behavior of environment friendly vegetable based oils as emerging biodegradable lubricants. The influences of the vegetable oils on friction and wear performance using different Tribometers were reported. The review focuses efforts on the development and commercialization of these vegetable based oils as industrial lubricants for manufacturing industries, mainly, metal forming and metal cutting. The review reveals that, many vegetable oils can be used as industrial lubricant, due to their exemplary attributes in terms of friction and wear reduction, which would help to decrease the universal demand of commercial lubricants which are based on petroleum resources to a great extent.