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Cet article traite de la fabrication et de la datation des ornements, outils et boites en laiton produits par les Akan dans les régions côtières du Ghana, en particulier les mforowa (sing. forowa), récipients en feuilles de laiton spécifiques utilisés pour y conserver le beurre de karité et qui sont associés à des rituels mortuaires. Les fouilles archéologiques ont permis de retrouver une variété d’artefacts fabriqués localement à partir de laiton européen importé, souvent en étroite association avec des objets de traite européens. Comme les gammes de production de nombreuses manufactures européennes sont connues et peuvent être bien circonscrites dans le temps – souvent à quelques décennies près –, les marchandises de traite offrent un moyen de dater précisément les artefacts qui leur sont associés et de manière plus assurée que ce qui est souvent possible pour les sites archéologiques africains des 500 dernières années. Cet affinage chronologique apporte un élément nouveau sur les traditions de travail des alliages de cuivre parmi les Akan côtiers, en particulier l’utilisation et la réutilisation du laiton importé. Cet article passe en revue les connaissances actuelles sur les origines de la métallurgie et la transformation du métal dans la région côtière du Ghana, et sur le développement du travail du laiton avec l’avènement du commerce européen. Les données archéologiques provenant de la ville africaine d’Elmina suggèrent que la production de mforowa a débuté au xviie siècle et que ses origines stylistiques trouvent leurs racines dans la tradition antérieure des nkuduo (sing. kuduo) en laiton coulé. Le contexte des découvertes archéologiques fournit également un aperçu des cadres culturels dans lesquels les mforowa ont été utilisés. This article discusses the manufacture and age of brass and other copper alloy ornaments, implements, and containers produced by the Akan of coastal Ghana, particularly mforowa (sg. forowa), distinctive sheet brass vessels used as containers for shea butter and associated with mortuary rituals. Archaeological excavations have recovered a variety of artifacts locally made from imported European brass in close association with European trade materials. Because the production ranges of many European manufactures are well known and can be closely dated—often within decades—they afford a means of more closely dating associated artifacts than is often possible on African archaeological sites of the past 500 years. This chronological control provides new insights into brass working traditions of the coastal Akan, particularly the use and reuse of imported brass. This article reviews current information on the origins of metallurgy and metal working in coastal Ghana, and the expansion of brass working with the advent of the European trade. Archaeological data from the African settlement of Elmina and other sites in the coastal hinterland support suggestions that mforowa production began during the 17th century and, further, that the stylistic origins of mforowa lie with the earlier nkuduo (sg. kuduo) brass casting tradition. The context of the archaeological finds also provides insight into the cultural settings in which mforowa functioned.

The objective of this paper is to determine whether it is possible to compare the lubricating properties of different Metal working fluids (MWF) for a defined cutting application using easily reproducible tribological tests. The idea is that this will eventually allow users of MWF to select the most suitable MWF for a specific application without the need to run expensive and time-consuming tests on a machine tool being unavailable for production during that time. The test method chosen is the Pin-on-Disc (PoD) test, as there has been extensive research and an easy setup can be acquired inexpensively, making it more available and attractive for potential users. The PoD-tests were done with two groups of MWF, those for wet machining and those for minimum quantity lubrication (MQL). Additionally, the viscosity of the MQL-MWF has been measured using a capillary viscometer. The evaluation of the wear on the pins and discs with different measuring devices shows consistent and promising results for the comparison of MQL-MWF, while the MWF for wet machining display only limited comparability with the PoD-setup used.

This article compares UK labour productivity during the Great Depression (GD) and the Great Recession (GR) in engineering, metal working, and allied industries. Over the downturn of the GD cycle, hourly labour productivity was countercyclical. Over the GR downturn, hourly productivity was procyclical. The combined flexibility of workers and hours, together with short-run diminishing returns, is argued to be the main drivers behind the GD productivity outcomes. There was less workers and hours responsiveness in the GR downturn. These differences are linked to educational and human capital arguments. Employers’ real-wage costs feature importantly in both depressions. In the GD, real hourly product wages rose steeply serving to encourage shorter work weeks, which produced positive impacts on average hourly labour productivity. Unusually, high-labour supply pressures in the GR acted to reduce real hourly product wages serving to protect the jobs of less efficient workers and to lower average hourly labour productivity.

The settlement of people in Lachin district that located in the foothills of the Lesser Caucasus dates back to ancient times. The settlements of the district were built mainly in accordance with tribal relations. The construction of villages in the area was mainly divided into mountainous, foothill, hill-side and plain types according to the relief of the region. On the whole, since Lachin district is located in a mountainous area, the construction of villages here was also different: mainly, the houses in the district were built far apart, mostly scattered; villages with hut dwellings and those with dwellings built compact, closer to each other.The newly built bines (nomad camps or isolated farmsteads) were named after those who built them first. Although the main occupation of the district population was animal husbandry, they were also engaged in gardening, forestry and beekeeping. Archaeological and ethnographic investigations conducted in the district, clarified that the population were engaged in many handicraft areas (pottery, stone carving, metal working, etc.). At the same time, the settlements, grave monuments, churches and tombs and bridges of the district were comprehensively studied. The district located in a mountainous area, covers one town, one settlement and 125 villages.

Palatial economic archives from various regions — from the Aegean world to Mesopotamia — and from various periods of the Bronze Age, attest to the use by palatial administrations of procedures in which workers were obliged to perform a task, whether craft or agricultural, on behalf of the palace. This article examines the possibility that such a procedure existed also in Ugarit, since a group of administrative texts relating to metals appear comparable to these systems of work-assignments. The material from Ugarit and the conclusions reached allow, then, a comparison with the system of work-assignment attested in the Mycenaean texts and called ta-ra-si-ja. Mycenaean and Ugaritic documentations present typological, structural and chronological analogies, which add to the interest of the comparison., Cet article est le produit du projet « Bureaucracy and Administrative Procedures in the Syrian Kingdom of Ugarit (14th to 12th centuries B.C.) » (FFI2015–67357–P) (MINECO/FEDER, UE), financé par le Ministerio de Economía, Industria y Competitividad au sein du Plan Estatal de Investigación Científica y Técnica y de Innovación (I+D+I) [J.-P.Vita], ainsi que du projet collectif « Palais de l’âge du Bronze en Egée et en Orient » de l’UMR 7041 du CNRS [Fr. Rougemont].

We present a survey of the main specific features of the continuous casting of billets of copper-based alloys with small cross sections. It is possible to significantly increase the efficiency and reduce the cost of production of lengthy semifinished products made of nonferrous alloys either by replacing the process of deformation by continuous casting or by significantly decreasing the cross sections of the billets intended for plastic metal working. It is shown that, for the major part of alloys, the process of upward continuous casting has numerous technological, economic, and metallurgical advantages as compared with other procedures of drawing. We also describe the regularities of solidification of the billets and formation of defects in the course of upward continuous casting, the specific features of design of the mold, the requirements to the properties of the graphitic jacket of the mold, and the characteristics of the modes of casting depending on the properties of the alloys.

Metalworking fluids (MWF) are mainly emulsions of oil in water containing additives such as corrosion inhibitors, emulsifiers, defoamers, and biocides. Microbial contamination of MWF is almost systematic, and some of their constituents serve as nutrients for contaminating microorganisms. Biocides for MWF are protection products used to counter microbial contaminations and growth. Ideally, a biocide for MWF should have the following non-exhaustive criteria: have a broad-spectrum activity, be usable at low concentrations, be compatible with the formulation and the physical-chemical properties of MWF, be stable over time, retain its effectiveness in the presence of soiling, have no corrosive action on metals, present no danger to humans and the environment, be inexpensive. The future lies in the development of new molecules with biocidal activity corresponding to these ideal specifications, but in the meantime, it is possible to improve the performance of existing molecules currently on the market. Different strategies for potentiation of the activity of existing biocides are possible. The compatibility of the potentiation strategies with their use in metal working fluids is discussed.

The production of semi-finished products made of refractory metals is considered. The advantage of parts production using combination of two types of straining with change in the straining direction: direct extrusion and equal-channel pressing is shown. The experimental investigation data of pure and simple shear for the semi-finished products processing made of tungsten and molybdenum are presented. Requirements for the tool providing diagonal flow and angular straining are formulated based on the analysis of the stress-strain state of the processes of axial symmetric extrusion and simple shear of plastically inhomogeneous body. Effectiveness evaluation of the combination of various types of fixtures and the rational sequence for using of diagonal flow and angular pressing is given. Experimental devices for practical application of the proposed technology are developed.

The article is devoted to description of changes in traditional metallurgy of Daghestan in connection with the development of Russian industry in the first half of the ХIХ century, the development of new technologies of metal processing in the province (locksmith business, etc.). There is an expansion of directions in the assortment of metal products, which appeared in Daghestan in the second half of the XIX – the beginning of the XX centuries. Many processes are illustrated by examples from the craft history of the famous Harbuk blacksmith center.

The results of a study of a metal working in environments causing hydrogen sulfide cracking are presented. The previously studied steels were induced in a hydrogen sulfide-containing medium under the action of tensile stresses in the metal of the samples. It has been established that characteristic defects in the form of bubbles and blisters are formed on the surface of metals. A study of microstructures showed that cracks originate at the boundary between pearlite and ferrite grains and on the streaked sulfide phase of the FeS · MnS type. Disclosure of the boundary of pearlitic and ferrite grains is due to their surface contamination with microimpurities. The results of the analysis for inclusions show that 20YuCH steel is much cleaner in inclusions than American steel of the type steel 20, and sulfides are more dispersed and coagulated, while a significant part of the sulfur is bound by cerium. This explains the best resistance of steel 20YUCH against hydrogen sulfide cracking.

Introduction. The paper considers the mathematical analysis of the fractional composition of dust generated during the operation of the rail-cutting machine. It is established that the studied polydisperse material is well described by the one-parameter exponential distribution. At the same time, the lognormal particle size distribution, whose parameters are determined by mathematical programming methods, seems adequate for the purposes of calculating cyclones. The work objective was to develop mathematical methods for correct averaging of the size and mass parameters of dust under the solid metal machining.Materials and Methods. We studied the possibility of approximating experimental data by Rosin – Rammler distributions (classical, generalized three-parameter P(x, D, n, m), and simplified exponential P(x), in which n = 1). The corresponding results were compared to each other and to the data of approximation of the lognormal and double lognormal functions. These results indicate close approximation quality using the following model distributions P(x):• five-parameter double lognormal;• three-parameter type of Rosin-Rammler;• two-parameter classical Rosin - Rammler;• one-parameter exponential.Results. The primary physical analysis of cutting waste was carried out by the laboratory measuring complex Fritsch Analysette 22 Compact which uses the LALLS – low angle laser scattering method. The built-in software provides output of measurement results in primary graphic and digital forms. It was found that the simplest exponential distribution is best suited for a detailed analysis of the dust particle-size distribution based on the experimental data.This distribution enables reproduction of all the integral indicators provided by the instrumental measuring complex along with the graphical data.Discussion and Conclusions. The results obtained can be used to rationalize the local suction machine, and the mathematical models and algorithms can be used for the parametric analysis of any dust captured by cyclones.

Recently, as the quality of life of modern people improves, interest in environmental noise is gradually increasing. As the public's awareness of environmental rights increased, it was necessary to grasp the actual condition of the noise source and systematic noise management plan. The data is expected to be used as a response to noise-related complaints. As a result measured using the factory noise monitoring system, the amount of data measured every 5 minutes from 00:00 to 24:00 can obtain 288 noise levels and frequency characteristics per day, and frequency using 1/3 octave-band. The analysis reveals what frequency range affects the noise from the metal working plant near the office. In addition, it can be seen that it is possible to compare with the reference value by using the stored data divided into night time, day time, and evening time for each time zone, and it is determined that it is possible to secure smooth data about the noise source to be measured.

The ever-increasing awareness of the environmental and health hazards of petroleum and mineral-oil-based metalworking fluids (MWFs) is forcing the scientist and tribologists to develop alternative MWFs. Mineral and petroleum-oil based MWFs are also considered non-biodegradable which hinders their successful implementation in metal machining which requires regular disposal of used cutting fluids. On the other hand, vegetable-oil based MWFs are considered as sustainable green metalworking fluids/lubricants which are biodegradable and have superior cooling and lubricating properties. A review is done on current literature which shows that vegetable-oil based MWFs are not only better alternatives considering its eco-friendly nature but also offers better machining performance by enhancing the cutting tool lifetime and minimizing the cutting tool/workpiece interface temperature, friction and surface roughness. Different cutting methods like dry machining, flood cutting, and minimum quantity lubrication techniques are compared for a better understanding of the reported studies.

The enhancement of resource efficiency in the manufacturing industry is a major key to achieve sustainable development. The purpose of this paper is to investigate the resource efficiency of metal working processes using different lubrication strategies: flood lubrication (FL) and minimum quantity lubrication (MQL). Life Cycle Assessment (LCA) is a suitable methodology to assess the resource efficiency. In this paper a LCA is carried out for three different materials: aluminium, steel and cast iron. The process related data had been provided by practical measurements on state of the art machines and missing data derived from literature and expert interviews. The used input and output data for the inventory analysis is documented in this paper. In a hotspot analysis using LCA, fourteen impact categories from CML 2001 had been analysed. Finally, parameters with a high influence on the resource efficiency of machining processes were examined. The results of the LCA show that the significant parameters causing high environmental impacts are electricity, compressed air and FL oil. The comparison of the machining processes using FL and MQL technologies reveals that most of the analysed processes have a higher environmental impact using FL instead of MQL. This is mainly due to the high energy consumption for the lubricating pump and also because of the higher consumption of lubricants compared to MQL. Furthermore, the generation of hazardous waste, in form of used oil and used filter fleece also contributes. The MQL-technology requires less electricity and lubrication oil and avoids hazardous waste. However, the results show that the compressed air consumption of MQL is significantly higher compared to FL-related processes. Through this study, new and specific LCA datasets for drilling and milling for three working materials including two lubricating strategies (FL and MQL) are generated for further research.

Copper alloys have important industrial roles due to their excellent properties. Beryllium copper is one of the copper-based alloys with the highest strength and excellent metal working and machining properties. Beryllium copper alloy composite is fabricated by the stir casting method. Its characteristics are studied with scanning electron microscopy and energy dispersive analysis of X-rays. The material properties of the stir cast beryllium copper alloy composites are evaluated. Hardness can be increased by the addition of silicon carbide particles. Abrasive water jet machining is an effective unconventional machining process, in which high pressure water jet and abrasive particles are used to remove material. Response parameters such as material removal rate and circularity of holes are considered. Response parameters of abrasive water jet machining are compared to electrical discharge machining. The most influential factor for the responses is determined by analysis of variance. Optimization of machining parameters is performed with the Taguchi method.

The aim of this research is to evaluate the tribological characteristics of the electroless Ni–B film under extreme pressure conditions, with coating thickness of 3 μm, 6 μm, and 12 μm in the as-plated condition and with incorporation of heat treatment (HT) (200 °C by 90 min). An electroless method is employed for Ni–B coating deposition on D2 tool steel specimens. A synthetic fluid was used as a lubricant, with a water–oil ratio of 10:1. Tribological evaluations were performed on a block-on-ring configuration according to ITEePib Polish method for testing lubricants under conditions of scuffing. Results indicate that electroless technology improved the coefficient of friction (COF) of the tool steel, ranging from 15 to 30%, with 3 μm to 12 μm of coating, respectively. This enhancement was increased by applying a heat treatment to the coated components, showing improvements of 24–38% with 3 mm to 12 mm, respectively. It is also observed that wear of the evaluated coupons also showed improvements ranging from 35 to 60%. These results demonstrate the potential of an electroless technique on materials suitable for metal-forming tooling and components, while decreasing friction and wear of mechanical components.

Orientador: Maria Helena Robert Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica These (docteur) - Universite de Savoie, Ecole Superiore D'Ingenieurs D'Annecy, France Resumo: Este trabalho apresenta estudo sobre a viabilidade da estampagem, no estado semisólido, de chapas da liga A5052. Inicialmente, para a obtenção de chapas tixofundidas, chapas comerciais laminadas foram submetidas ao processo de fusão parcial controlada, variando-se os parâmetros tempo e temperatura, com o objetivo de analisar a estampabilidade das chapas no estado sólido. Os parâmetros utilizados foram: fusão parcial a 627°C por 5 e 10 minutos, e 634°C, por 5 e 15 minutos, em chapas com 0,8 mm; fusão parcial a 624°C por 5 e 10 minutos, e 631°C por 5 e 15 minutos, em chapas com 2,0 mm; e fusão parcial a 625, 630 e 635°C por 15 minutos em chapas de 4,0 mm de espessura. As chapas foram caracterizadas com relação à microestrutura, sendo observada homogeneidade estrutural em toda a chapa. Também foram caracterizadas quanto às propriedades mecânicas, sendo que o material tixofundido (obtido por fusão parcial) apresentou diferenças significativas em relação ao material laminado. Para a caracterização da estampabilidade do material, foram feitos ensaios de Erichsen e obtidas curvas limite de conformação de chapas nos estados laminado, recozido e tixofundido, utilizando o método Marciniak e um método de análise de imagens para a obtenção das deformações principais da liga nos diferentes estados. Os resultados mostraram que o material tixofundido apresenta formabilidade semelhante à do material recozido. Foi buscada a caracterização do arranjo espacial de glóbulos em pastas tixofundidas; os resultados mostraram a presença de aglomerados tridimensionais de partículas com evidente interação entre elas, indicando a possibilidade da estrutura suportar esforços de tração. Portanto, para estudos da viabilidade de tixoestampagem, foi construída matriz com geometria tal a apresentar condições severas de conformação. As chapas foram tixoestampadas (temperaturas acima da solidus) e comparadas com chapas estampadas a quente. Observou-se que a tixoestampagem é um processo perfeitamente viável, levando a excelentes resultados de acabamento da peça e redução da força necessária para a obtenção do produto Abstract: This work presents an analysis of the viability of drawing A5052 sheets in the semisolid state. Initially, to produce thixocast sheets, rolled commercial sheets were submitted to partial melting by different temperatures and holding times, to analyse the sheets draw ability in the solid state. The parameters utilised were: 627°C for 5 and 10 minutes, and 634°C, for 5 and 15 minutes, in sheets of 0,8 mm; 624°C for 5 and 10 minutes, and 631°C for 5 and 15 minutes, in sheets of 2,0 mm; and 625, 630 and 635°C for 15 minutes in sheets of 4,0 mm thickness. The sheets had their microstructure characterised; results showed high homogeneity of the structure throughout the test piece. Mechanical properties of the thixocast material (obtained by partial melting) were also characterised, showing significant differences when compared to the rolled condition. For drawing ability characterisation, Erichsen tests were performed and forming limit diagrams of the sheets in the rolled, annealed and thixocast states were obtained, using Marciniak's technique and image analysis to obtain the main deformations of the alloy in the different conditions. Results showed that the thixocast material shows good formability, similar to the annealed material. Characterisation of the spatial structure of thixocast slurry showed the presence of tridimensional agglomerates of globular solid particles, with evident interaction among globules, indicating the possibility of the structure to stand tensile stresses. Therefore, for thixodrawing tests, a die was especially designed to impose severe flow conditions. The sheets were formed by thixodrawing (temperatures above the solidus) and compared to hot drawing tests. It was observed that thixodrawing is a perfectly viable process, requiring lower forces than conventional solid processing and resulting in excellent finishing products Doutorado Materiais e Processos de Fabricação Doutor em Engenharia Mecânica

The efficiency of cold steel rolling depends mainly on the quality of the metal-working coolant (MWC) and its cost. In this connection, it is actual to search for new compositions of lubricants and emulsions, which provide the lowest values of the friction coefficients in deformation zone and are obtained by waste recycling in other industries. In this study we have developed new compositions of the MWC on basis of mono- and diglycerides and their esters of boric acid synthesized from the wastes of sunflower oil production. The new compositions of MWC were tested in DSEA on laboratory rolling mill 100x100 with a roll diameter of 100 mm. The efficiency of new MWC during cold rolling of brass L63 samples was determined by factor of metal stretch forming λ. We found the new metal-working coolants to show the most efficiency under higher cobbing that provides the highest metal stretch forming. The composition with 30 % of mono- and diglycerides is the most effective because it provides the minimum coefficient of friction that leads to increase of factor of metal stretch forming. Thereby the metal-working coolants on basis of mono- and diglycerides obtained from the wastes of sunflower oil production can be recommended for use in strip rolling of copper-zinc alloys because of a low cost, availability and high efficiency.

There has been increasing recognition that education is not limited to what the children are taught through traditional education and that cognitive processes may be broader than those taught and tested in school. This study aims to design a video game that improves students’ engagement and motivation on the most important Pre Inca cultures. Most of the Pre Inca civilizations are worldwide recognized for the quality of their fine textiles, temple construction and stone sculptures and fine metal working of copper, gold, silver. Our research focuses on using the amusing nature of video games to get the students involved into topics that may include many elements to remember and retain for students. The motivation and interest generated from a video game involves that the student can not only remember the information and characters within the game, but also that they get involved with the content of the game and have the initiative to ask or know more about it, and the result is active learning instead of passive learning.

Fraud has over the past decade become an epidemic, impacting not only Ghana as a country or Africa as a continent but the whole world. It has proven to be a most challenging criminal act to tackle and address and hence has left many nations stunned. In Ghana Fraud accounts for about 47.7% of victimization rate in Ghana as was recorded in a 2010 report issued by the United Nations Office of Drugs and Crime (UNODC,2010). It has since then towered in severity, manifolds. In response to this increasing menace, the need arose to establish the Economic and Organized Crime Office (EOCO). This was because the “responsibility and management of fraud as well as corruption could no longer be left to police and other quasi anti-crime organizations alone. However, with the increasing sophistication of society, complex frauds and other economic crimes, EOCO despite many efforts has even become more widespread. Education and sensitization of the masses has become ever more needed in the prevention and detection of fraud. The project hence is an attempt to contribute to the education of the public regarding the severity of fraud and the need to be aware and vigilant in regards fraudulent tricks and antics through metal art. It employs various metal working methods and techniques in creating an amazing metal art which serves as an effective communicative tool for creating awareness on the psychology behind fraudulent acts in general and in particular Ghana. The production of this art piece further, exposes and widens the practical application and creativity of metal artists. DOI: 10.7176/ADS/89-01 Publication date: January 31 st 2021

The article analyzes the learning process of the students of the machine-building industry. It is established that engineering thinking occupies a special place among professional competences needed for the successful professional activity of a technical specialist. The aim of the article is to analyze the peculiarities of forming the professional competence of future specialists of the machine-building industry during the study of the topic "Safe construction of high-speed spindle units on the pneumatic supports". Studying of this topic provides acquiring by the students the knowledge and skills of designing of efficient and safe elements of the mechanical equipment. First of all the stress is made on the safety of the machines and mechanisms for metal working, being designed. This stipulates the proposal to use pneumatic supports for spindle units, which are designed for high-speed machine-tools of high precision and allow to increase the rigidity and technological capabilities of the spindle at its high efficiency and satisfy the requirements of electrical, explosion and fire-safety, allowing students to form the culture of safety, which is decisive for the formation of professional competence. We believe that the proposed method of calculating the pneumatic supports with the required static stability of its equilibrium position ensures their efficient and safe use, as well as generates technical thinking and professional competence of future specialists. In addition, this technique of forming technical thinking while studying the topic of safe construction of high-speed spindle units on pneumatic supports, in the conditions of the reduction of time for training of future specialists of the machine-building industry, allows moving from the reproductive training to searching training.

Realization of photo-electrochemical water splitting to generate H2 alternative fuel requires the facilitation of the kinetically-sluggish oxygen evolution reaction (OER) occurring at the photoanode. To do so, there is a need to develop new methods to assemble suitable OER co-catalysts at the semiconductor–solution interface. Although Metal–Organic Frameworks (MOFs) are frequently used as precursor materials to synthesize high surface area, effective OER electrocatalysts, until now their utilization as co-catalysts in a working photo-electrochemical cell (PEC) has remained underexplored. As a proof-of-concept, here we provide a simple route for modification of BiVO4-based photoanodes with highly-active porous cobalt-oxide co-catalysts, converted from a cobalt–imidazolium MOF (ZIF-67). Photo-electrochemical and impedance spectroscopy analysis reveal that the co-catalyst significantly accelerates photoanodic OER (rather than serving as a surface passivation layer), and thus greatly improves the overall PEC performance. Hence, given the chemical flexibility of MOFs, this work provides a new tool-kit for designing efficient water splitting PECs.

Fundamentals of the complex approach to the experimental investigations of metal-working technological systems to ensure parameters of quality and operation properties of machinery surfaces are considered. The approach mentioned above is applicable both at the stage of scientific researches and under conditions of experimental-technological laboratories of manufacturing enterprises. It embraces the matters of planning, and also metrological, mathematical and instrumental support of investigations.

Lubricating oils are used throughout the economy. This comprises lubricant types such as engine oils, compressor oils, hydraulic oils, machine oils, and metal working oils among other types. Succeeding their intended use span, a relevant share of lubricating oils can be recovered as waste oils which need to be treated as hazardous waste. In the EU, a legal and institutional framework has been established to ensure a high-quality recycling and a disposal that is compatible with the best public interest. To periodically evaluate the efficacy of the legal framework and its implementation in the EU member states, the end-of-life situation of waste oils needs to be investigated periodically. So far, there is no consistent method for the (retrospective) evaluation of the efficacy of the legal framework which can be adapted by the single states. In this article, a methodological framework for the analysis of waste oil flows on a country level is presented. While this framework explicitly focuses on the situation in the EU, its application to non-EU member states is possible, but potential differences in the availability of required input data need to be considered thoroughly. The presented calculation model is exemplarily applied to the situation in Germany and Belgium in 2015. In Germany about three quarters of the collected waste oil go to (domestic) re-refining. In Belgium, most waste oil is exported and re-refined abroad.

Fluorescence spectroscopy experiments are a frequently taught as part of upper-division teaching laboratories. To expose undergraduate students to an applied fluorescence technique, a corrosion detection method, using quenching, was adapted from authentic research for an instrumental analysis laboratory. In the experiment, students acquire fluorescence spectra of sensing molecules in the presence of mock sculpture samples and discuss the condition of the sculptures based on the levels of soluble iron detected. This real-world-based experiment allows students the chance to engage with ongoing research and further understand the challenges with early detection of corrosion. Most students successfully completed the experiment, wrote a journal-quality report, and met the learning outcomes.

This work resumes first results concerning the identification of workers’ inhalation exposure by means of workplace measurements in the field of additive manufacturing. In particular for powder-bed processes, risks caused by mixed exposures due to released particles and relevant chemical constituents or possible volatile compounds have to be evaluated. The workplace measurements are focused on processes in the automotive as well as the aviation and tool construction industry. The aim is to gain exposure data concerning the application of metal-containing powders and alloys as well as polymer powders in powder-bed processes and to derive instructions for good working practice.

The use of metal working fluids widespread with the industrial revolution in the late century. Petroleum based cutting fluid were being extensively used in the machining area causing health and ecological-related issues. The present work tried to elaborate the performance of eco-friendly and user-friendly karanja oil in water based cutting fluid during orthogonal cutting of AISI 1045 steel. Further attempt has been made to identify influence of developed and conventional cutting fluid on chip formation. Based on the findings of the study, a great reduction of 11% was observed in chips thickness which significantly increases tool life.

Cold drawing is metal working process utilising tensile forces to deform the metal. This paper reports the microstructure and mechanical properties correlation with each stage of multi-pass cold drawing of ST 35 steel in the process of seamless tubes manufacturing. The microstructural evaluations showed that there is grain elongations as the number of passes increases. The same findings can be validated using Scan Electron Microscope (SEM). In addition, the mechanical testing values on UTM are examined with the number of passes. The results of this study shows that the mechanical properties, variation in grain size and hardness has correlation with the resulting microstructure of the material which are evaluated with the increase in number of passes. First pass before heat treatment shows better properties.

Metal working fluids represent a threat for workers and for the environment. In this paper an innovative technological and preventive approach is presented relying on the substitution of the base fluids with natural vegetable oil based esters. The results confirmed similar or better technical features of these fluids and a significant reduction of air pollution in particular for polycyclic aromatics. An innovative selective hydrogenation process to improve the oxidative stability of rapeseed oil is also presented. In this way a very significant increase in the oxidative stability of the parent oil, determined by Rotary Bomb Oxidative Test, was observed. The hydrogenated oil is even more stable than High Oleic Sunflower Oil while keeping acceptable cold properties.

Until today cutting processes were mainly optimized by trial and error to increase yield and surface quality. However, optimization of the cutting process, e.g. reduction of the saw kerf width, improvement of surface quality as well as tool optimization, requires a basic understanding of the interaction between tool and workpiece. However, knowledge-based optimization of cutting processes is lacking from a valid cutting model considering the complex and inhomogeneous structure of wood. Subsequently, out of this analytical description an applicable semi-empirical model, likewise in the metal working industry, is necessary. But, the validation of a cutting force model requires the existence of consistent cutting force values. However, utilization of data from previous studies is impossible as important information about data processing, cutting parameters as well as wood properties is lacking. To enable a validation of the cutting force model, a standardized and reliable method for the examination o...

An innovative application of Mobile Metal Ion (MMI) partial extraction soil geochemistry is used to identify below-surface archaeological features, using a previously incompletely surveyed Roman metal-working site at St. Algar's Farm, Somerset, as a case study. Soil samples were taken and analyzed for 53 elements by the MMI geochemical method. Lead, Tl, Ba, and Zn were found in very high concentrations and the sensitivity of the technique also enabled Ag, Au, and Sn to be measured in anomalous concentrations. Elemental maps accurately outlined known metal working areas. Principal component analysis and bivariate correlations identified two suites of associated elements: Pb, Ba, Tl, Ag, Au, Cu, Sb, the base and noble metal group (BNM), and Fe, Ti, Nb, Mn, Co, Cu, P, Li, Rb, Sc, Cs, K, Ga, P, Zr, Th, and Sn, the pegmatite (PEG) group. These were used to form indices that delineate the metal working area and areas possibly related to the processing of pegmatite containing Sn. The high-sensitivity MMI data were compared with strong acid digest results from a limited number of the MMI samples; the MMI data showed better geochemical contrast than the strong acid results. Multielement statistical similarity comparisons with off-site samples suggest likely sources for the Pb and Sn used at the St. Algar's site. The increased sensitivity of MMI soil analysis combined with the multielement capacity allows a more detailed archaeological interpretation.

Introducing systems capable of profound reduction in a casting and rolling module improves the product quality, on account of the intense working of large continuous-cast slabs over the whole cross section and the production of uniform fine-grain structure of the metal, and also increases the cross section of continuous- cast billet. Analysis of the formation of nonmetallic inclusions and segregation in the axial zone of the thick rolled sheet is followed by analysis of the nonuniform deformation over the slag height in the reduction of large continuous-cast slabs at the 5000 mill at OAO Magnitogorskii Metallurgicheskii Kombinat. The structure of a cyclic-deformation system for preliminary deformation of large continuous-cast slabs is described, and its capabilities are explored. Hammers for preliminary deformation of large continuous-cast slabs are considered. Experimental data are presented for the deformation of continuous-cast steel 45 and 12Kh18N10T steel billet. The structure of the continuous-cast billet is assessed in the course of reduction on the cyclic-deformation system. The basic parameters of the system for preliminary deformation of large continuous- cast slabs are determined. The capabilities of the cyclic-deformation system are outlined in terms of increase in sheet quality. On that basis, the use of the cyclic-deformation system in the continuous-casting line for preliminary reduction of large continuous-cast slabs is recommended: it permits matching of the speed of continuous-casting and cyclic-deformation processes; and ensures 45–90% reduction in a single pass so as to obtain well-worked cast structure over the whole slab cross section. When using the cyclic-deformation system in the continuous-casting line, the continuous-cast slabs are reduced by means of the heat of the cast metal, thereby greatly reducing the energy consumption in billet production. The cyclic-deformation system may be used with thick-sheet and broad-strip mills for preliminary single-pass reduction of the hot slab, with improvement in sheet quality and reduction in the number of passes in the mills. © 2017, Allerton Press, Inc.

In several OECD countries employer federations and unions fix skill-specific wage floors for all workers in an industry. One view of those “explicit” contracts argues that the prevailing wage structure reflects the labor market conditions back at the time when those contracts were bargained, with little space for renegotiation. An alternative view stresses that only workers close to the minima are affected by wage floors and that the wage structure reacts to current labor market conditions. We disentangle both models using a novel data set that combines more tan 1,000 signature dates and 15,000 wage floors set in the metal working industry with labor market histories of metal workers drawn from Social Security records in Italy and Spain. An increase in the contemporaneous local unemployment rate of 1 p.p. diminished contemporaneous mean wages by about 0.45 p.p. between 2005 and 2013 in both countries. Instead, a 1 p.p. higher unemployment rate back at the time of contract renewal reduced wages by 0.7 p.p., an impact driven by wages close to the negotiated wage floors. Even though the evidence for earlier periods is mixed in Italy, the results do not support the view that the wage structure reflects labor market conditions at the time of bargaining. The results support the hypothesis that (most) wages respond to local current unemployment rate, although the estimated elasticity falls short of the prediction of an off-the-shelf bargaining model.

Metal Working Fluids (MWF) are crucial for both lubrication and cooling during operation of machinery processes. MWF undergo changes over time due to various factors such as evaporation or the growth of bacteria. Due to these changes, a variety of additives are added over the service life of the fluids to ensure that the properties remain at the optimum for the end-user. At present, MWF assessments are carried out using either hand-held devices or using automatic analysis systems. Manual assessment is done at best once a week which results in irregular testing and deterioration of fluids. Whilst the automated systems available can analyze the parameters without human intervention, they lack predictive capabilities and still require operators to dose and pour the additives. MWF and additives both pose occupational health risks to the workers. During metalworking, the degraded MWF affects the quality of the metal piece; the life of the equipment tool and the health of the workers. A present, there are no artificial intelligence technology systems available on the market able to autonomously predict fluid degradation events and manage the fluids themselves. We propose an automated system able to fulfill the above-mentioned specs, also developing an IA algorithm able to produce a forecast concerning the WMF degradation over time, in order to develop an adequate predictive maintenance.

A comprehensive analysis of the archival literature on sustainable (i.e., socioeconomic, and environmental friendly) machining of advanced aerospace materials and composites has been performed. Specifically, the paper focuses on the techniques to improve the machinability of difficult to cut materials (Steel alloys, Ni-based super alloys, Ti-based alloys, and composites) frequently consume in aerospace manufacturing industry. The current industrial requirement on high-performance sustainable machining of advanced super alloys and composites have been addressed for the machining process optimization to gain reasonable profit margin. Here, the specific interest areas are formulation of high-performance vegetable oil-based metalworking fluid (MWF), health and environmental conscious machining of difficult to cut materials and future perspectives on biodegradable MWFs on machining advanced aerospace materials and composites. The proposed approaches of the sustainable and cleaner production for the above-mentioned areas involves the occupational health and safety, minimum waste (i.e., effluent) generation, elimination of the environment pollution (i.e., MWF usage and disposal phases) and high-performance machining. Additionally, the influence of tribological properties of vegetable oil based MWFs on thermophysical characteristics of difficult to cut materials have been critically reviewed. The study presented in the paper is timely valuable due to the rapid increment of the demand on sustainable machining requirement in difficult to cut materials. Moreover, the presented comprehensive analysis, proposed suggestions and recommendations will help the next generation scientists to find the recent advances as well as future avenues of research on high performance sustainable machining of advanced aerospace materials and composites (i.e., category of difficult to cut materials) to ensure process optimization and industrial sustainability.

A new study concludes that one of the world9s earliest metal working cultures emerged, and then mysteriously faded, far earlier than once thought. The Old Copper Culture, known for using copper to craft projectile points, knives, axes, and other tools, flourished around North America9s Great Lakes more than 5000 years ago. Early Native Americans left behind thousands of mines and countless copper artifacts, including a spear point that is 8500 years old. A new analysis of radiocarbon dates of those artifacts, as well as an analysis of lake sediments holding evidence of ancient mining, shows that the Old Copper Culture likely began earlier than once believed, about 9500 years ago, and also faded earlier, about 5000 years ago. Other research suggests a regional climate shift might have catalyzed cultural changes that prompted Native Americans to stop making many utilitarian tools out of copper and use the material more for adornment.

Sintered cemented carbides are very important for modern engineering. It is difficult to point out an industry having no interest in cemented carbides. Their unique properties – hardness, strength, wear resistance, scale resistance, high temperature strength, corrosive resistance – make them suitable for different applications such as metal working, oil-well drilling, mining industry, chipless machining, arms industry, nuclear, space, vacuum and electric engineering, instrumentation, synthetic diamond fabrication process, etc. This paper provides an overview of domestic cemented carbide evolution and fabrication stages. The contribution of national researchers to the development of various cemented carbide grades and their fabrication progress is shown. The outstanding role of Professor G.A. Meerson in the cemented carbide industry development is mentioned. The paper cites the results of many Russian and CIS researchers from such leading institutes as the Russian National Cemented Carbide Research Institute (Moscow, Russia), Ukrainian Institute of Materials Science (Kiev, Ukraine), Institute for Superhard Materials (Kiev, Ukraine), Ural Branch of the Russian Academy of Science (Kirovograd, Russia), Ural Polytechnic Institute (Ekaterinburg, Russia), Tomsk Polytechnic Institute (Tomsk, Russia), Belarusian Institute of Powder Metallurgy (Minsk, Belarus), Institute of Metallurgy and Materials Science (Moscow, Russia), Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences (Chernogolovka, Russia).

Fluids play a major role for production machinery and serve for very different tasks as lubricating, tempering, cleaning, transmitting force and energy. Due to maintenance requirements and the environmental impact their utilization is under discussion and alternatives are looked for. In this paper an overview of the latest research activities in the field of fluidic elements on machine tools is presented. The topic of the paper includes an overview of the fluids used in machine tools, the usage of fluidic elements, supply and treatment units, and their influence on machine tools performance. A link to fluidic media on energy efficiency is given. Research challenges in order to increase the performance of machine tools are discussed. The paper excludes metal working fluids, which have been treated in Brinksmeier et al. [33].

Steel strips are frequently used in the metal working industry for the manufacturing of tubes and bearing sleeves. These steel strips are produced by cold and warm rolling and are commonly coiled up for transportation purposes. Moreover, the obtained coils are split into customized sizes. In order to use the steel strips for further processing the edges need to be machined with respect to deburring and joint preparation. Therefore, specialized machine tools are used which apply common turning inserts with a translational cutting motion. On the one hand this process is high efficient but on the other hand the process reliability is affected by the formation of long continuous chips. In order to meet the requirements for an increased process reliability investigations on chip flow control are carried out with the aid of the finite element method (FEM). The acquired results are presented in this article.

Short-chain chlorinated paraffins (SCCPs) show high persistence, bioaccumulation potential, and toxicity (PBT properties). Consequently, restrictions on production and use have been enforced in several countries/regions. The Stockholm Convention on Persistent Organic Pollutants recognized the PBT properties and long-range transport potential of SCCPs in 2015 and is now evaluating a possible global phase-out or restrictions. In this context, it is relevant to know which countries are producing/using SCCPs and in which amounts, and which applications contribute most to their environmental emissions. To provide a first comprehensive overview, we review and integrate all publicly available data on the global production and use of both chlorinated paraffins (CPs) as a whole and specifically SCCPs. Considerable amount of data on production/use of CPs and SCCPs are missing. Based on the available data and reported emission factors, we estimate the past and current worldwide SCCP emissions from individual applications. Using the available data as a minimum scenario, we conclude: (i) SCCP production and use is increasing, with the current worldwide production volume being 165,000t/year at least, whereas the global production of total CPs exceeds 1milliont/year. (ii) The worldwide release of SCCPs from their production and use to air, surface water, and soil between 1935 and 2012 has been in the range of 1690-41,400t, 1660-105,000t, and 9460-81,000t, respectively. (iii) The SCCP manufacture and use in PVC, the use in metal working applications and sealants/adhesives, and the use in plastics and rubber contribute most to the emissions to air, surface water, and soil. Thus, the decrease in the environmental emissions of SCCPs requires reduction of SCCP use in (almost) all applications. (iv) Emissions due to the disposal of waste SCCPs cannot be accurately estimated, because relevant information is missing. Instead, we conduct a scenario analysis to provide some insights into it.