5 research outputs found

    Fabrication of various micropatterns by maskless micro-electrochemical texturing

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    In this paper, an innovative and alternative concept of maskless micro-electrochemical texturing is exploited for the fabrication of simple and complex micropatterns. In this process, the tool is masked incorporated with the textured patterns and the workpiece has no mask. This research study concentrates on generation of simple micropattern, i.e. linear micropattern, and complex micropattern, i.e. cascade micropattern using maskless micro-electrochemical texturing method without repeated use of photolithography process. A single masked patterned tool with SU-8 2150 mask can produce many high-quality simple and complex micropatterns economically using this method. A well-planned experimental set-up consisting of electrochemical micromachining (EMM) cell, electrode fixtures, electrical connections and constricted vertical cross-flow electrolyte system has been designed and developed indigenously for carrying out the experiments. Influences of major influencing parameters, i.e. machining voltage, interelectrode gap, flow rate and machining time, are investigated on width overcut and machining depth of micropatterns. For higher machining accuracy, controlled depth and lower standard deviations, machining with lower machining time, lower voltage, lower interelectrode gap and higher flow rate is recommended. From the detailed experimental investigation, the best parametric combination are voltage of 8 V, duty ratio of 30%, pulse frequency of 15 kHz, electrolyte of NaCl (0.34 M) + NaNO3 (0.23 M), flow rate of 5.35 m3/h, interelectrode gap of 50 µm and machining time of 40 s

    Physical characterization of modified palm oil with hybrid additives nanofluids

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    The common use of petroleum-based metalworking fluids (MWFs) in industry harms the environment and human beings. The biggest disadvantage of RBD palm oil is its low thermal-oxidative stability. As a result, the goal of this research is to create an innovation for palm oil based MWFs. The new creation of modified palm oils (MPOs) has been produced by a transesterification process with palm methyl ester to trimethylolpropane molar ratios of 3.5:1. Later, at a concentration of 0.025wt.%, the MPOs were mixed with single and hybrid additives such as activated carbon (AC) (MPOa), tungsten disulphide (WS2) (MPOw) and hybrid AC with WS2 (MPOaw). The physicochemical parameters of MPOs were studied, including viscosity, and acid value. The physicochemical properties were evaluated as per ASTM standards over a period of 4 weeks to check the state of lubricant and observable changes in the properties during this period According to the findings, MPOaw shows enhanced thermal (high viscosity index 365-387) and oxidative stability (lubricant storage). Moreover, MPOaw recorded has higher antioxidant properties that can help prevent or slow down the oxidation process, reducing the production of acids and subsequently lowering the acid value (0.14 -0.19 mg NaOH/g). In conclusion, it has been proven that MPOaw has the best performance and the potential to have a positive effect on the industry as a sustainable MWF for machining processes

    Antecedents and outcomes of brand management from the perspective of resource based view (RBV) theory

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    Brand management requires greater emphasis on internal factors to increase brand performance. A model of antecedents and outcomes of brand management is developed in this study based on the Resource Based View (RBV) Theory. Top management emphasis on brand, corporate supportive resources and market orientation are identified as crucial internal factors or antecedents for success of brand management. Apart from that, the brand management measurement are expanded in this study with the introduction of three new marketing constructs namely marketing capabilities, innovation and brand orientation as new dimensions in brand management which currently comprised of management related constructs. This study also contributes in the brand management of small and medium enterprise (SMEs) literature as previous studies mainly focused on the brand management for multinational companies or large organizations. One important issue of SMEs is the “internal” brand management which is currently under-researched even though it is critical in brand building and management. Therefore, this research aims to highlight the antecedents and outcomes of brand management in Malaysians’ SMEs based on RBV theory. A comprehensive literature review was done and a conceptual model is proposed in this literature review

    Physical properties of new formulation of hybrid nanofluid-based Minimum Quantity Lubrication (MQL) from modified jatropha oil as metalworking fluid

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    As a metalworking fluid, vegetable-based crude jatropha oil (CJO) was used in place of petroleum-based oil. The use of petroleum-oil-based metalworking fluids poses significant environmental and health concerns. Furthermore, it has a large amount of free fatty acid (FFA), promoting physical damage. This research targets to substantially evaluate the modified jatropha nanofluids formulation as a metalworking fluid for machining processes. CJO was chemically altered using the esterification and transesterification processes to produce modified jatropha oil (MJO). To make the nanofluids, MJO was mixed with nanoparticles of Hexagonal Boron Nitride (hBN) + Tungsten Disulfide (WS2) and Hexagonal Boron Nitride (hBN) + Titanium Dioxide (TiO2) at a concentration of 0.025 wt.%. The viscosity and acid value of MJO nanofluids were assessed using ASTM standards and compared to a synthetic ester (SE). All the data indicates that the physical attributes improved throughout storage. It is possible to conclude that MJOhw (MJO + 0.025 wt.% hBN + WS2) has the ability as a long-term metalworking fluid for the machining operation. According to the experiment results, MJOhw surpasses non-additive MJO in terms of kinematic viscosity by 5.91% at 40 °C and 15.6% at 100 °C. During a one-month duration of storage time, MJOhw also improve viscosity index (319) by 18.15%. Furthermore,MJOhw has an acid value ranging from 0.34 to 0.58 mg NaOH/g. Finally, the inclusion of additives aids MJO in improving its qualities by 31.1% reduction in acid value and MJOhw demonstrates outstanding lubricating properties across all samples
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