Current Materials Science - Volume 14, Issue 1, 2021

Objective: This paper represents a bibliometric analysis of additive manufacturing throughout the history. In this paper, major statistical insights regarding the publications associated with additive manufacturing are presented. These insights are categorized on the basis of authors, publication source titles, country, document types, research areas, etc. Results: This study differentiates crucial research fields, critical journals, and significant authors that have contributed to the field of additive manufacturing and 3D printing. Conclusion: This overview can guide researchers in exploring literature related to additive manufacturing and 3D printing in a meaningful direction. Moreover, some future aspects regarding additive manufacturing are also discussed in the conclusion.

Background: Minimum quantity lubrication (MQL) is one of the most promising machining techniques that can yield a reduction in consumption of cutting fluid by more than 90 % while ensuring the surface quality and tool life. The significance of the MQL in machining makes it imperative to consolidate and analyse the current direction and status of research in MQL. Objective: This study aims to assess global research publication trends and hot topics in the field of MQL among machining processes. The bibliometric and descriptive analysis are the tools that the investigation aims to use for the data analysis of related literature collected from Scopus databases. Methods: Various performance parameters are extracted, such as document types and languages of publication, annual scientific production, total documents, total citations, and citations per article. The top 20 of the most relevant and productive sources, authors, affiliations, countries, word cloud, and word dynamics are assessed. The graphical visualisation of the bibliometric data is presented in terms of bibliographic coupling, citation, and co-citation network. Results: The investigation reveals that the International Journal of Machine Tools and Manufacture (2611 citations, 31 h-index) is the most productive journal that publishes on MQL. The most productive institution is the University of Michigan (32 publications), the most cited country is Germany (1879 citations), and the most productive country in MQL is China (124 publications). The study shows that ‘Cryogenic Machining’, ‘Sustainable Machining’, ‘Sustainability’, ‘Nanofluid’ and ‘Titanium alloy’ are the most recent keywords and indications of the hot topics and future research directions in the MQL field. Conclusion: The analysis finds that MQL is progressing in publications and emerging with issues that are strongly associated with the research. This study is expected to help the researchers to find the most current research areas through the author’s keywords and future research directions in MQL and thereby expand their research interests.

Background: Synthesis of metallic nanoparticles has attracted extensive vitality in numerous research areas such as drug delivery, biomedicine, catalysis, etc., where continuous efforts are being made by scientists and engineers to investigate new dimensions for both technological and industrial advancements. Amongst numerous metallic nanoparticles, silver nanoparticle (AgNPs) is a novel metal species with low toxicity, higher stability and significant chemical, physical and biological properties. Methods: In this, various methods for the fabrication of AgNPs are summarized. Importantly, we concentrated on the role of reducing agents of different plant parts, various working conditions, such as AgNO3 concentration, ratio of AgNO3/extract, incubation time, centrifugal conditions, size and shapes. Results: This study suggested that eco-friendly and non-toxic biomolecules present in the extracts (e.g., leaf, stem and root) of plants are used as reducing and capping agents for silver nanoparticles fabrication. This method of fabrication of silver nanoparticles using plants extracts is comparatively cost-effective and simple. A silver salt is simply reduced by biomolecules present in the extracts of these plants. In this review, we have emphasized the synthesis and antibacterial potential of silver nanoparticles using various plant extracts. Conclusion: Fabrication of silver nanoparticles using plant extracts has an advantage over the other physical methods, as it is safe, eco-friendly and simple to use. Plants have huge potential for the fabrication of silver nanoparticles of wide potential applications with the desired shape and size.

The objective of this study is to carry out a literature review on the effect of friction drilling parameters on the mechanical and metallurgical properties of materials. The friction drilling process uses heat generated by friction between the workpiece and the tool. In a single step, tool penetrates into the work material, forming a circular hole and forms bushing without generating chips. Bushing acts as a structural scaffold and guide to assemble sheet metal parts without the need for separate threaded parts. This review focuses on the basics of friction drilling, advantages, applications, metallurgical and mechanical properties of the tool and materials. Tools reviewed in this research are high speed steel (HSS) and AISI H13 chromium hot work steel. The study observes that coated friction drilling tool life is more than uncoated friction drilling tool. At higher spindle speed and feed rate, good quality hole is produced with maximum bushing height and better surface finish.

Background: The value of the activation energy is dependent on deformation conditions and sensitive to the difference in the alloying element. The research on the evolution of the activation energy with strain and alloying elements plays an important role in analyzing the mechanism of hot deformation. Objective: The purpose was to clarify the activation energy evolution with strain, to analyze the strengthening or softening mechanism of each element, and acquire an empirical equation for medium carbon steels to quantitatively describe the effect of each element on activation energy. Methods: Hot compression tests of the two medium carbon steel were conducted. The value of activation energy at different strain was obtained by fitting the experiment results. Through the analysis of medium carbon steels with different compositions in published papers, the empirical relationship between thermal activation energy and chemical composition can be fitted. Results: It was found that the activation energy showed significant dependence on the strain and chemical composition. The activation energy’s evolution with strain was revealed. An empirical expression for medium carbon steels was proposed to characterize the influence of the chemical composition on the activation energy. It was found that the microalloying elements Nb, Ti, V and Mo, as the main solution strengthener and precipitation strengthener, have a positive effect on the activation energy. Conclusion: The evolution of the activation energy with strain was revealed, and the corresponding hot deformation mechanism was analyzed through the activation energy. An empirical expression was acquired to characterize the influence of the chemical composition on the activation energy for medium carbon steels, which would be used for the research on new materials.

Background: Chrome shavings, a bioactive material, are generated from tannery as waste material. These chrome shavings can be used for the preparation of many value-added products. Objective: One such attempt is made to use these chrome shaving wastes as a composite biobattery to produce DC voltage, an alternative green energy source and cleaner technology. Methods: Chrome shavings were hydrolyzed to make collagen paste and mixed with the ferrous nanoparticles of Moringa oleifera leaves and carbon nanoparticles of onion peels to form electrolyte paste as the base. Then, the electrolyte base was added to the aluminum paste and conducting gel, and mixed well to form a composite material for bio-battery. Results: The composite material of bio-battery has been characterized using Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA). Series and parallel circuit testing were done using copper and zinc electrodes or carbon and zinc electrodes as the battery terminals in the electrolyte paste. The surface area of these electrodes needed standardization from bench to pilot scale. The power generated, for an AA battery size, using a single bio-battery cell produced a DC voltage of 1.5 V; current of 900 mA. Circuit testing on 1 ml of 80 well-cells connected in series produced DC output of 18 V and 1100 mA, whereas 48 V and 1500 mA were obtained from a series-parallel connection. Conclusion: The glass transition temperature (Tg) of electrolyte of the bio-battery at 53°C indicated that at this temperature, all the substances present in the bio-battery were well spread and consistently contributed to the electrolyte activity where Fe-C-nano-particles were able to form strong chemical bonds on the flanking hydroxyl group sites of the collagen leading to reduced mobility of polymers and increased Tg. The results instigate promising trends for commercial exploitation of this composite for bio-battery production.