Metal Tools Research Articles

Heavy Metals Content in Great Shearwater (Ardenna Gravis): Accumulation, Distribution and Biomarkers of Effect in Different Tissues.

The purpose of this study was to explore the usefulness of Great Shearwater (Ardenna gravis) as a bioindicator for biomonitoring programs for metal pollution. Three different metals were analysed in liver, kidney, and feathers, including cadmium, lead, and zinc. Glutathione-S-transferase, malondialdehyde, reduced glutathione, and catalase were assessed as oxidative stress biomarkers. Sex-related trends in metal accumulation also were evaluated. In liver and kidney, the mean concentrations of Zn (146.1 ± 5.14 and 108 ± 2.70mg/kg, respectively) and Pb (0.19 ± 0.01 and 0.13 ± 0.01mg/kg, respectively) in A. gravis were generally comparable to values reported in other studies. However, animals presented slightly higher concentrations of Cd (9.67 ± 0.65 in liver and 17.41 ± 0.84mg/kg in kidney) than those reported in the same species sampled in Southern Atlantic waters. The slightly higher levels of Cd found in this study compared with other studies are probably affected by the location in Northern Atlantic waters (with different diet intake). In feathers, levels of Zn (70.70 ± 1.76mg/kg) were lower than in other Ardenna shearwaters, whereas higher levels were found for Cd (0.16 ± 0.01mg/kg) and Pb (0.84 ± 0.06mg/kg). The lack of differences found between males and females could be influenced by the migration status, because both sexes stay in similar physiological conditions, with no laying eggs. Levels found in the feathers of the present study were related to concentrations in internal tissues below those which cause adverse effects in birds. Thus, feathers would appear as a potential noninvasive tool for metals biomonitoring in seabirds, because it is possible to quantify them. Baseline data of oxidative stress levels have been reported, both in liver and kidney, presenting no correlations with the levels of metals in these tissues. The low internal metal levels and the lack of correlations between oxidative stress metrics suggest a low risk of the environmental concentrations for seabirds.

Precious Metals in the Worldview System of Ancient Iranian-Speaking Peoples on the Texts of Avesta

An overview and contextual-semantic analysis of the cases of usage the lexeme ‘gold’ (zaraniia-) and ‘silver’ (ərəzata-) in corpus of Avestan sources (Yasna, Yashts, Videvdat, Aogəmadaēca, etc.) are provided in the article. ‘Gold’ is used in the Avesta 101 times. ‘Silver’ — only 12 uses, while this metal is always contextually linked with gold. Silver has a semantic connection with the aquatic sphere. Gold is the material from which, according to the texts, the garments of several deities are made (Vayu, Aredvi Sura (partially)). Gold attributes or decorated with this metal tools have a number of gods and heroes (Yima, Mithra, Verethragna, Tishtria, Sraosha) are made completely or partially from it. In the myth of Yima, the divine instruments, the golden suβrā and gilded aštrā, are endowed with reproductive features and help to create the first kingdom (Videvdat 2.6—38). This ideal mythical world turns into the Afterworld. A set of semantic attributes show that gold is directly related to the Otherworld, where the souls of the righteous deceased receive gold places, golden or silver clothes (Videvdat 19.31—32; Aog. 12, 17). The fact that silver and other «colors» are added to gold may indicate the expansion of the spectrum of precious metals and their penetration into the sphere of funeral beliefs. In the treatise of Aogəmadaēca (84), silver-gold (a metaphor of wealth), along with cattle, horses and bravery, is included in the system of concepts related to the Thanatological worldview of the pre-Zoroastrian representations of ancient Iranian tribes.

Comparative Study of Electrical Discharge Machining, Electrical Discharge Drilling and Electrical Discharge Diamond Drilling of Nimonic 75

Due to wide range of applicability of hard and difficult-to-machine materials like super-alloys (Ti-alloys, Inconel, and Haste-alloy etc), advanced ceramics, composite materials, and high technical characteristics of above-mentioned materials, suitable advanced machining processes are conducted. EDM is one of the most popular advanced machining processes. But the EDM process has low metal removal rate (MRR) so EDD is another machining process as it has relatively higher MRR as compared to EDM. Here electric discharge diamond drilling (EDDD), a hybrid-EDM process comes into the picture in order to improve the machining performance characteristics. The present research aimed to compare the process performance in electrical discharge cutting, drilling and diamond abrasive drilling. The effects of process parameters such as peak current (I), pulse-on time (Ton), and pulse-off time (Toff) were studied on metal removal rate (MRR) and tool wear rate (TWR) in electrical discharge diamond drilling of Nimonic 75.

Evaluation of ANN and ANFIS modeling ability in the prediction of AISI 1050 steel machining performance

In the development of an accurate modeling technique for the design of an efficient machining process, manufacturers must be able to identify the most suitable technique capable of producing a fast and accurate performance. This study evaluates the performance of the Artificial Neural Network (ANN) and Adaptive Neuro-Fuzzy Inference System (ANFIS) models in predicting the machining responses (metal removal rate and tool wear) in an AIS steel turning operation. With data generated from carefully designed machining experimentation, the adequacies of the ANN and ANFIS techniques in modeling and predicting the responses were carefully analyzed and compared. Both techniques displayed excellent abilities in predicting the responses of the machining process. However, a comparison of both techniques indicates that ANN is relatively superior to the ANFIS techniques, considering the accuracy of its results in terms of the prediction errors obtained for the ANN and ANFIS of 6.1% and 11.5% for the MRR and 4.1% and 7.2% for the Tool wear respectively. The coefficient of correlation (R2) obtained from the analysis further confirms the preference of the ANN with a maximum value of 92.1% recorded using the ANN compared to that of the ANFIS of 73%. The experiment further reveals that the performance of the ANN technique can yield the most ideal results when the right parameters are employed.

A bivariate fatigue-life regression model and its application to fracture of metallic tools

The Birnbaum–Saunders distribution has been widely used to model reliability and fatigue data. In this paper, we propose a regression of generalized linear models type based on a new bivariate Birnbaum–Saunders distribution. This is parameterized in terms of its means and allows data to be described in their original scale. We estimate the model parameters and carry out inference with the maximum likelihood method. A case study with real-world reliability data is conducted for motivating our investigation, illustrating the potential applications of the proposed results. We obtain a predictive model which can be a useful addition to the tool-kit of diverse practitioners, reliability engineers, applied statisticians, and data scientists.

Завершение исследований могильника Усть-Тартас-2 (Барабинская лесостепь)

In the field season of 2021, the studies at the Ust-Tartas-2 site were completed. They were based on geophysical monitoring; excavations were carried out using the method of continuous opening of the object area. In five years, 2250 sq. m have been unearthed. A sanctuary of the Early Neolithic Baraba culture had a system ofpits, ditch, joint pits which among other things contained art objects, and pits intended for keeping and fermenting fish. Seventy nine burials have been studied (seven of the Artyn culture of the Final Neolithic, two of the Ust-Tartas culture of the Early Metal Age, fifty seven of the Odino culture of the Early and Advanced Bronze Age, eight of the Krotovo culture of the Advanced Bronze Age, one of the Iron Age, and four of unidentified time). During the excavations of 2021, the cultural layer revealed pottery fragments, various artifacts made of stone, clay, and bone, and two metal tools. Several utility pits with animal and fish bones also contained fragments of pottery mostly belonging to the Pit-Comb historical and cultural community of the Early Metal Age, as well as pottery of the Bronze Age, and Late and Early Neolithic. Two burials (No. 78 and 79) have been investigated; their location indicated the Odinov culture as the time of their creation. In the northwestern part of excavations, an object (No. 21) consisting of three oppositely directed (to the south, west and north) elongated oval pits, connected at the bases by one pit, has been discovered. Fish bones were in the southern and western pits. There are two interpretations of functional purpose of the object: 1) arched ditch bounding the Odinov part of the burial ground with a fish smokery cutting into it; 2) three-chamber fish smokery. A particularly significantfind of the field season was a bone sculpture of elk’s head, which did not clearly belong to any specific complex. According to the predominance of the pit-comb pottery of the Early Bronze Age in the cultural horizon, the sculpture may be related to this period.

Опыт проведения археологических наблюдений на участке культурного слоя города Томска в 2020 году

This article describes the results of rescue archaeological works at the site of archaeological heritage “Section of the cultural layer of the city of Tomsk on Altaiskaya St., 6, second half of the 19th - early 20th centuries,” in the area of constructing apartment building. The site is located in the central part of Tomsk (historical region) on the left bank of the Ushaika River (right tributary of the Tom River). In the course of archaeological observations, fundamentally new information on stratigraphic and planigraphic context of the site was obtained. A collection of archaeological objects (831 artifacts), including fragments of pottery, porcelain dishware, earthenware, meta dishware and glassware, leather and birch bark shoes, metal tools, jewelry and household items, coins, glazed and unglazed clay tiles, and cast-iron gravestone was collected in the destroyed cultural layer. The complex of things dates back to the period from 1830 to 1910, and enriches our understanding of various aspects of everyday life in Tomsk at that time. During archaeological observations, areas of undisturbed cultural layer at that site of archaeological heritage have not been found. As a special type of archaeological field works, archaeological observations make it possible to successfully employ the entire set of methodological tools available to archaeologists, focus on archaeologically promising sites, and accelerate works on unpromising or ruined areas.

3D printing to facilitate flexible sheet metal forming production

This study presents and discusses the possibility of using 3D printed polymer tools to achieve a flexible metal forming production line. An example is given of the design of a sheet metal part from tool printing to the actual forming and evaluation of the achieved precision of the formed part. The time spent by the engineer/operator during the full process cycle is documented and compared to the time it would take to make the corresponding tool by conventional metal machining. The time savings revealed in the paper are relevant for a low number of parts to be formed in a flexible manufacturing environment, while it is less relevant in mass production where metal forming is conventionally an attractive process. Besides the time invested by the engineer/operator, it is also important to keep the costs of the tools at a minimum in flexible manufacturing. Therefore, the paper also presents a comparison of the costs for printed tools as compared to conventional tools made from metal machining. This analysis considers the cost of raw materials, machine time and electricity consumption. The environmental aspects of metal forming are also considered, with the lubricating oils and greases typically used to improve frictional conditions being replaced by the polymers, which themselves have anti-friction properties. Finally, the recyclability of the tools is significant when they are only used to form a few parts. Different types of polymers and printing strategies are discussed in relation to recyclability and compared to the alternative metal tools.

Комплексы позднего периода набильской археологической культуры (северо-восточный Сахалин)

The article analyzes the archaeological materials of the two Nabil dwellings located on the sand spit, which separates one of the largest lagoons in the north-eastern part of Sakhalin Island from the Sea of Okhotsk. The researched archaeological objects are presented by pit dwellings with entrances in the form of a corridor-crawlway. The objects are synchronized, and they have C14 calibration age within the 4th –2nd century BC. During the existence of the settlement (the climate boundary was between Sub-Boreal and Sub-Atlantic phases) the climate was a little warmer than the modern one. The objects were located in the favourable fishing area of the island. The household complexes of the dwellings are similar. The Nabil’s pottery has foreign cultural influence and it is differentiated from the Early Nabil complexes. There are a lot of stone tools intended for the fishery. The stone tools were locally produced. There are both the stone tools and the corroded metal fragments and the stone replica of the metal tools. The Nabil jewelry is of transit origin and it shows the presence of relationships between South Sakhalin and the continental areas of Far East. It is assumed that in the conditions of a shortage of metals, the need for its import caused the integration of the peoples of Sakhalin into the system of regional trade and exchange relations. Keywords: Sakhalin Island, Paleometal age, Nabil culture, pit dwelling, pointed shape pottery, stone tools, tubular beads, iron Acknowledgements: The author is grateful to her teachers and colleagues Doctor of History Alexander A. Vasilevsky and Candidate of History Vyacheslav A. Grishchenko for critical and suggestive remarks that contributed to a broader understanding of the sources.

A qualitative study on cutting tool materials for bone surgeries

Open reduction internal fixation is a kind of orthopaedic surgery that repairs broken bones from serious accidents or injuries. This procedure is considered for severe bone fractures which cannot be treated by a non-invasive procedure such as splint or cast. Implants such as screws, plates, and nails help to reposition and realign the broken bone fragments internally. An Orthopaedic Drilling is performed on the bones to create enough space to place the implants, and also it will generate enough heat to damage the bone cells, leading to osteonecrosis. This paper aims to present the researched survey report on proposing ceramic cutting tools (drill bit, cutting saw, and burrs) to be introduced in orthopaedic surgeries. A quantitative survey was conducted on 25 orthopaedic surgeons based on a questionnaire regarding cutting tool type, tool material, tool life per surgeries, tool performance, and scope of improvements. In support of the objective, another survey was conducted on 50 tool manufacturers around the world. Survey results showed that almost every surgeon uses the metal-based cutting tool for surgeries; based on that requirement, manufacturers produce metal-based cutting tools. Metal tool properties and proposed ceramic properties comparison is showcased, resulting in Ceramics properties exceeds in almost every property compared to stainless steel, Titanium, and other cutting tool properties.

A study of metallurgical and processing approach of additive layer manufacturing processes for metal tool components production

Additive Layer Manufacturing (ALM), also known as 3D printing technology process of manufacturing that refers models parts from wire, powder, or sheets in a process that produced layer-by-layer from computer aided manufacturing (CAM). This process enables to produce components via solid-state joining or melting process. In this paper, these methods for producing metal tool components production through processing study of ALM methods as heat transfer, processing defects, solidification, mechanical properties, solid-state precipitation and post-processing metallurgical study. The various metal ALM techniques are analysed and compared with analysis of their strengths and limitations. Most of the metal alloys fabricated and produced and developed for production of metal tool components, but recent development of ALM shows as a path for the producing and development of new materials for additive layer manufacturing processes.

Performance Improvement: A Lean Manufacturing Case of Metal Tools Factory

Performance Improvement: A Lean Manufacturing Case of Metal Tools Factory

The Bronze age amber industry in northern Italy in light of high-resolution 3D imaging

We summarize here the preliminary results of the experimental application of high-resolution 3D imaging to the study and reconstruction of the chaîne opératoire of amber bead-making in the northern Italian peninsula in the 2nd millennium BC. Amber, an unusually soft raw material that is highly sensible to any kind of physical and chemical change, records a spectrum of archaeological information that was almost unimaginable until recently. We show how the examination of manufacturing waste and finished beads using opto-digital microscope and laser scanning confocal microscope (LSCM), and considering the interactions with post-manufacturing use-wear traces, reveals unexpected evidence about the beads’ biography, emphasizing, in first place, the probable important role of the heat-treatment of amber with metal tools.

Experimental evaluation of nickel and cobalt release from tools and self-reported prevalence of nickel and cobalt allergy in the German hairdressing trade.

Nickel release from some metal tools in the hairdressing trade has been sporadically evidenced, whereas data about cobalt release from metal tools in the hairdressing trade are lacking. To screen metal tools for nickel and cobalt release and to estimate the prevalence of nickel allergy and cobalt allergy in the German hairdressing trade. Four hundred seventy-five metal tools in the hairdressing trade were tested in three North German states with a nickel spot test for nickel release and with a cobalt spot test for cobalt release. Seventy hairdressers were surveyed with a standardized questionnaire to collect data about the tested metal tools as well as the prevalence of nickel allergy and cobalt allergy. One hundred thirty-one of 475 metal tools (27.6%) - 60 of 60 hair clips (100%), five of five crochet hooks (100%), 24 of 40 tweezers (60.0%), 33 of 75 sectioning clips (44.0%), five of 32 straight razors (15.6%), and four of 45 tail combs (8.9%) - released nickel and 10 of 475 metal tools (2.1%) - three of 40 tweezers (7.5%), four of 60 hair clips (6.7%), one of 32 straight razors (3.1%), and two of 75 sectioning clips (2.7%) - released cobalt. Eight of 63 female hairdressers (12.7%) suffered from nickel allergy and two of 63 female hairdressers (3.2%) suffered from cobalt allergy. Metal tools in the German hairdressing trade - with which a prolonged skin contact is intended - release nickel and cobalt in allergologically relevant amounts and thus should be taken into account as occupational sources of exposure to nickel and cobalt.

Metal Tools in Unpublished Cuneiform Texts from Early Dynastic Period

عرف سكان بلاد الرافدين معادن كثيرة وعرفوا طرائق تصنيعها واستعمالها ودخلت في الكثير من أعمالهم وصناعاتهم ، حتى في مجال انتاج الأعمال الفنية والأدوات والآلات الزراعية وأسلحتهم، ومن أهم هذه المعادن الذهب والفضة والنحاس والقصدير التي دخلت في عمل سبائك البرونز وغيرها ، وقد اجتهد سكان بلاد الرافدين القدماء في الحصول على خامات المعادن فكانوا يتحملون أعباء السفر والمتاعب في جلب الخامات من أماكن عديدة وكان من بينها دلمون (البحرين) وماكان (عمان) وميلوخا ومصر وبلاد الأناضول .

ОПРЕДЕЛЕНИЕ ОСНОВНЫХ СВОЙСТВ ПЫЛЕВЫХ ЧАСТИЦ ЗАТОЧНОГО УЧАСТКА

The abrasive processing of metal products is accompanied by harmful dust emissions into the work area. Exceeding the MPC of dust particles in the work area has a negative impact on the health of working personnel-it leads to occupational diseases of dust etiology. To localize harmful dust emissions when working on grinding machines, there are various dust collectors and their modifications, which allow to deal with harmful dust emissions with different efficiency. The design of the dust collector shrouds may involve connecting to an aspiration system that creates a low-pressure zone in the housing of the shroud, and thereby helps to remove harmful particles released during work. To correctly calculate the costs of air removed by local suction systems, it is necessary to analyze the dust situation and determine the properties of dust aerosols at a specific enterprise. In this work, the analysis of samples of dust particles selected at the grinding site of the plant for the manufacture of metal-cutting and metal tools, as well as technological equipment of LLC Production Company "Russian tool". Obtaining correct and up-to-date data on the size and chemical analysis of dust particles is necessary for the development of an energy-efficient aspiration system, as well as a mathematical model of the movement of dust particles.

Discrete Friction Mechanisms of a Metal Tool with Polycrystalline Diamond-Coated Detail

Discrete Friction Mechanisms of a Metal Tool with Polycrystalline Diamond-Coated Detail

Tribological Behavior of AlCrSiN-Coated Tool Steel K340 Versus Popular Tool Steel Grades.

The tribological performance of metalwork steel tools is of vital importance in both cold and hot working processes. One solution for improving metal tool life is the application of coatings. This paper investigates the differences in quantitative wear behavior and wear mechanisms between AlCrSiN-coated and bare steel K340 and five reference tool steels: X155CrVMo12-1, X37CrMoV5-1, X40CrMoV5-1, 40CrMnMo7 and 90MnCrV8. The investigated tool steels were heat-treated, while K340 was subjected to thermochemical treatment and then coated with an AlCrSiN hard film (K340/AlCrSiN). The hardness, chemical composition, phase structure and microstructure of steels K340 and K340/AlCrSiN were examined. Tribological tests were conducted using the ball-on-disc tester in compliance with the ASTM G99 standard. The tests were performed under dry unidirectional sliding conditions, using an Al2O3 ball as a counterbody. The wear factor and coefficient of friction were estimated and analyzed with respect to hardness and alloying composition of the materials under study. Scanning electron microscopy (SEM) observations were made to identify the sliding wear mechanisms of the analyzed tool steels and physical vapor deposition (PVD)- coated K340 steel. In contrast to the harsh abrasive–adhesive wear mechanism observed for uncoated tool steels, the abrasive wear dominates in case of the AlCrSiN. The deposited thin film effectively prevents the K340 substrate from harsh wear severe degradation. Moreover, thanks to the deposited coating, the K340/AlCrSiN sample has a coefficient of friction (COF) of 0.529 and a wear factor of K = 5.68 × 10−7 m3 N−1 m−1, while the COF of the reference tool steels ranges from 0.70 to 0.89 and their wear factor ranges from 1.68 × 10−5 to 3.67 × 10−5 m3 N−1 m−1. The AlCrSiN deposition reduces the wear of the K340 steel and improves its sliding properties, which makes it a promising method for prolonging the service life of metalwork tools.

한국 청동기-초기철기시대의 시기구분 -금속기의 출현과 정치체의 등장을 기준으로-

한국 청동기-초기철기시대의 시기구분 -금속기의 출현과 정치체의 등장을 기준으로-

Experimental Investigation of Deposition Pattern on the Temperature and Distortion of Direct Energy Deposition-Based Additive Manufactured Part

The effect of deposition pattern on the temperature and global distortion of Direct Metal Tooling (DMT) based Additive Manufactured (AM) is investigated through the experimental results of laser deposited SUS316. DMT is one of the Directed Energy Deposition (DED) processes. In situ temperature measurements were used to monitor the temperature of the substrates and global distortion patterns were analyzed using CMM (coordinate Measuring Machine) after the deposition. Six different patterns combining long raster and short raster patterns were considered for the case studies. The results showed that the deposition pattern affects the temperature gradient and that the peak temperature of each layer can increase or decrease according to the sequence of the deposition pattern. Also, the pattern of the first layer had a dominant influence on the longitudinal bending deflection that occurs. Based on these results, appropriate tool path schedule can be utilized to control not only the distortion but also the peak temperature of the DMT-based AM parts.