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Case Presentation A 74-year-old man was referred to a pulmonologist for evaluation of a 1-year history of nonproductive cough and progressive exertional dyspnea. He was initially evaluated by his primary care physician, where he had spirometry that was negative for any obstructive or restrictive lung disease. An echocardiogram showed a normal left ventricular ejection fraction, with no wall motion abnormality or valvular heart disease. He had an outpatient chest radiograph performed ( Fig 1 ), and he was subsequently treated empirically for a COPD exacerbation with 5 days of oral prednisone and azithromycin. He was eventually referred to a pulmonologist because of a lack of clinical improvement. On seeing his pulmonary physician, he described the same exertional dyspnea and a nonproductive cough. A review of systems was negative for fever, chills, wheezing, angina, arthralgia, myalgia, rash, or leg swelling. He denied any medical illness and was not taking any medications. He was currently retired and had worked as a cashier his entire adult life. He had no occupational exposure to asbestos, coal dust, beryllium, silica dust, or dust from hard metal objects, such as cobalt. However, he had smoked approximately 1 to 2 packs of cigarettes per day and had done so for the past 50 years. His vital signs were unremarkable, aside from an oxygen saturation of 94% on room air. His physical examination revealed bibasilar “velcro-like” inspiratory crackles on lung examination. There was no digital clubbing, nor was there peripheral edema in his lower extremities. He had no muscle tenderness and demonstrated normal muscle strength against resistance.

Hard metal lung disease (HMLD) is rarely diagnosed and is caused by the occupational inhalation of hard metal dust, mainly cobalt. The diagnosis of HMLD is based on a thorough occupational dust exposure combined with clinical–radiological–histological findings. We present a series of four Chinese workers who had occupational exposure to cobalt acid lithium or cobalt and tungsten dust. Four patients all complained of intermittent cough, chest tightness, or shortness of breath on exertion. High-resolution computed tomography scans presented bilateral ground-glass attenuation, consolidations, and/or reticular opacities with diffuse small nodules. Histologic findings showed that interstitial inflammation and fibrotic lesions distributed peribronchioles. The infiltrations by macrophages as well as visible multinucleated giant cells indicated giant cell interstitial pneumonia (GIP). Cobalt was detectable in the lung tissues of two patients measured by inductively-coupled plasma mass spectrometry. The first patient was diagnosed with cobalt-related interstitial lung disease (ILD), while the others were HMLD. GIP is the classic pathology of cobalt-related ILD or HMLD. One of the patients showed spontaneous remission after the cessation of exposure, while the other three recovered within 6–32 weeks after avoiding occupational exposure and using corticosteroids. At follow-up, all four patients showed no recurrence. A multidisciplinary diagnostic panel including occupational cobalt exposure evaluation is beneficial to recognize cobalt-related ILD or HMLD and to indicate the necessity of prevention.

The relation between pressing energy and green strength is examined experimentally and numerically using a commercially available design of experiment (DOE) software, at compaction of five hard metal powder materials. This is of substantial practical importance, in particular at pressing of complicated geometries when high values on the green strength is necessary. The compaction energy is here experimentally determined at uniaxial compaction of a cylindrical die, filled with powder material, by measuring punch force and compression. The corresponding measurements of the resulting green strength are performed using standard three-point bend (3PB) testing. The statistical analysis of the results shows that the relation between the two properties, pressing energy and green strength, is very close to a linear fit with the coefficient of determination R2 taking on the value 0.92. This suggests that the pressing energy is an important quantity for reaching a target value on the green strength and the linear relation is certainly convenient in particular when compaction of similar materials is at issue. In parallel with the experimental work finite element calculations are performed in order to evaluate the effect from friction between the powder and the die wall, and it was found that this feature has a limited effect on the pressing energy when similar materials are at issue and is not detrimental for the usefulness of the present correlation approach.

Objective To study the relationship between inhalable dust and cobalt, and respiratory symptoms, lung function, exhaled nitric oxide in expired air, and CC16 in the Swedish hard metal industry. Methods Personal sampling of inhalable dust and cobalt, and medical examination including blood sampling was performed for 72 workers. Exposure-response relationships were determined using logistic, linear, and mixed-model analysis. Results The average inhalable dust and cobalt concentrations were 0.079 and 0.0017 mg/m, respectively. Statistically significant increased serum levels of CC16 were determined when the high and low cumulative exposures for cobalt were compared. Nonsignificant exposure-response relationships were observed between cross-shift inhalable dust or cobalt exposures and asthma, nose dripping, and bronchitis. Conclusions Our findings suggest an exposure-response relationship between inhalable cumulative cobalt exposure and CC16 levels in blood, which may reflect an injury or a reparation process in the lungs.

In manufacture sector, the surface finish quality has considerable importance that can affect the functioning of a component, and possibly its cost. The surface quality is an significant parameter to evaluate the productivity of machine tools as well as machined components. It is also used as the critical quality indicator for the machined surface. In recent years the prediction of surface roughness has become an area of interest for machining industry. Cutting force, cutting temperature, tool wear, and vibration signals are some of the factors that can be used individually to predict surface roughness, but when it is used collectively a more accurate prediction of surface roughness is possible since each of the above-mentioned factors have their own characteristics effects of surface roughness. In the present study, an attempt was made to fuse cutting force, tool wear and displacement of tool vibration along with the cutting speed, feed and depth of cut to predict the surface roughness of hardened SS 410 steel (45 HRC) using a multicoated hard metal insert with a sculptured rake face. Regression models and an artificial neural network model were developed to fuse the cutting force, cutting temperature, tool wear and displacement of tool vibration to predict the surface roughness. From the results it was observed that the prediction of surface roughness by the artificial neural network had a higher accuracy than the regression model.

The high strength and high hard metal materials such as nickel-based superalloy have been widely used because of their excellent properties. If the gradient nanostructures are prepared on their surfaces, their properties will be further improved and their application will be expanded. In this paper, a coupled mechanical ultrasonic-electric pulse (CMUEP) treatment method is presented and its special pulse power source with high instantaneous energy density is developed. The power supply includes main circuit, gate turn-off thyristor (GTO) control circuit, switch control circuit, display circuit, etc. The CMUEP treatment of nickel-based superalloy is carried out by using this power source. The results show that grains with the average diameter of 25.8nm are prepared on Inconel 718 surface, which can further improve the properties of the high strength and high hard metal materials and broaden their application.

Processing metallic powders by electrical resistance sintering requires the use of insulating ceramics dies. Selecting the appropriate ceramic material according to the electrical, thermal and mechanical properties is a need. Dies produced with several ceramic materials have been tested during the production of cemented carbide in order to check their behaviour in the process and final product properties. Tialite/mullite, zircon/mullite, zirconium phosphate based ceramic, yttria-stabilized zirconia and sialon, in most cases with modified compositions and shaping processes in order to achieve a high density, have been tested. Dry powder processing by cold isostatic pressing and furnace sintering resulted to be the better process for dies production. The effect of die properties on the produced cemented carbide, and the behaviour and life of the die during the production have been analysed. Very smooth die surface increases the number of cycles withstood during metallic parts production, because of lower extraction stresses, as checked for sialon dies. Zirconium phosphate based dies, with low thermal conductivity, show the most densified hard metal parts surface.

White light interference (WLI) data of different metal materials subjected to laser shock show two surface topography characteristics: laser shock-generated circle indentions with flat bottom or circular arc bottom. The difference of surface topographies is mainly related to the mechanical properties of metal materials. Hard metal materials acquire indentions with flat bottom while indentions with circular arc bottom are obtained by soft metal materials, and the two different indention appearance features result in the differences of surface quality. The identification of the different indention topography types can serve as a selecting basis of overlapping rate.

WC-Co hard metals have proven to be excellent tool materials capable of coping with the elevated cyclic load levels that arise in e.g. metalworking tool application. The design of cyclically loaded tools requires reliable information on the fatigue behaviour of hard metals, also as a function of the acting mean stress. Since hard metals show defect controlled fracture behaviour, the nature of defects and their size distribution in the volume of given loaded structures is relevant to their fatigue behaviour. The concept of effectively loaded volume Veff allows for the comparison of the fracture probability of loaded structures with different kinds of stress distributions. To date, Veff of laboratory test setups and metalworking tools and its influence on the fatigue behaviour was not considered in the respective design processes. Instrumented milling experiments in combination with finite element based load analysis were used in the current work to provide information on typical values of stress ratio and Veff for end milling tools. A newly developed non-conventional type of a six point bending test setup was designed to induce values of Veff and mean stress which were found to be representative for the metalworking tool. The shape of the used central specimen support structures was designed to avoid contact damage to the specimen at the sites of load transfer. The knowledge-based design of the six point bending test setup assures that a region of the hard metal's bimodal defect size distribution is probed that leads to fatigue limits relevant to the failure behaviour of end milling tools.

In this work, the impact of temperature, pressure and gas flow on the chemical compositions, phases and deposition rates of MTCVD (Moderate Temperature Chemical Vapor Deposition) Ti(C,N) coatings is investigated by integrating thermodynamic calculations and computational fluid dynamics (CFD) simulations with key experiments. The thermodynamic calculations predict that both the C and the N contents of the films increase with increasing temperature under constant mixed gases and pressure, with the former increasing faster than the latter. CFD simulations indicate that the coating deposition rate decreases with increasing distance to the source gas for the hard metal samples loaded on the same tray. Subsequently, MTCVD-Ti(C,N) coatings were deposited at three different temperatures to verify the predicted chemical compositions and deposition rates. The experimental investigations are in reasonable agreement with the theoretical predictions. The present work applies a well-established strategy to meet the requirements of a controlled and robust process for MTCVD-Ti(C,N) coating with industrial applications.

Designed for aeronautical and automotive applications, the split sleeve cold expansion process is used to improve the fatigue life of bolted metallic parts. Although its application has been well tested on aluminum assemblies, hard metal applications are still being studied. This paper presents experimental results of double bolt joint assemblies under double shear fatigue tests after stacked split sleeve cold expansion. The behaviors of two sizes of assemblies with different degrees of expansion are investigated. S-N curves are the main indicators of this study but thermal aspects are also investigated to observe fretting in the specimens as bolts are preloaded. Bolt tension is a major parameter in assembly regarding fatigue life. Interference between those two phenomena is at the heart of this paper. The first results show that stacked cold expansion has a negative effect on mechanical performances, as it deteriorates the fatigue life of the assembly. However, an examination of these results provides a coherent explanation for the loss of performance that occurs.

The frequency and severity of respiratory disorders among workers exposed to hard metal dust is not well known.The objective of this cross-sectional study is to report the prevalence of respiratory symptoms, functional status, and radiological findings in hard metal-exposed workers in Turkiye.Among 139 workers, 96 were machining workers, and 43 were industrial tool sharpening workers. Radiographic abnormalities compatible with pneumoconiosis were found 39% of the workers and were more in machining workers statistically significant.Also, in machining workers group, percentage of expected values of FVC was lower than industrial tool sharpening workers group. The prevalence of respiratory symptoms was 14.3%, and there was not a statistically significant difference in working groups. The study reveals that pulmonary symptoms, functional abnormalities, and radiological findings are mild. Assuming that reversibility may develop with avoidance from exposure when detected at this stage, early diagnosis of lung damage is essential.

Bronchoscopy is a diagnosis and treatment method to examine and treat the tracheal and intrabronchial lesions through bronchoscopy. The endoscope has two types: one type is a hard metal hollow pipe which can observe every lobular bronchus; the other type is a fiberoptic bronchoscope, with a thin, soft and flexible tube body, sufficient lighting and clear images, it can be guided into several pulmonary segmental bronchi, and to diagnose the bronchial lesions, especially the early pulmonary cancer etc., the relatively harder tube is more convenient, because it causes less pain and it gains a better effect.

Objectives: Implant-supported restorations are generally used for the replacement of the lost teeth. Stability against masticatory forces and proper retention are critical for optimal durability of restorations. The aim of this experimental study was to compare the retention of cobalt-chromium (Co-Cr) copings made by different techniques. Materials and Methods: Twenty-four solid abutment analogs were mounted and scanned with a desktop scanner. They were divided into two groups (n=12) and received metal copings fabricated by either soft or hard Co-Cr alloy. Soft Cera­mill Sintron Co-Cr patterns were milled and sintered. Hard Co-Cr blocks were milled in a milling machine. The copings were sandblasted, polished, adjusted, and placed on the respective abutments. The frequency of adjustments was recorded for each abutment. The copings were cemented with zinc phosphate cement and underwent tensile test by a universal testing machine. The Mann-Whitney test and t-test were used to compare the two groups (α=0.05). Results: There was no significant difference in retention of copings between the experimental groups. The mean retentive force was 559.58±115.66 N and 557.13 ±130.48 N for the soft and hard metal groups, respectively (P=0.96). Considering the non-normal distribution of adjustment frequency data, the Mann-Whitney test showed that the frequency of adjustments was significantly higher in the hard metal group than the soft metal group (9.5 versus 0.1667; P

Pulmonary fibrosis is a progressive lungs disease which usually gets worse over time. Once this disease damages the lungs, it cannot be cured totally. But early detection and proper diagnosis can help to keep this disease in control. It causes scarring in the lungs over time. As an effect, people face breathing difficulty. It can cause shortness of breath, even at rest. The general causes of pulmonary fibrosis can be exposure to toxic element like coal dust, asbestos fibres, silica dust, hard metal dusts etc. But in majority of the cases, the doctor cannot figure out the exact cause of this disease. That's why this disease is termed as Idiopathic Pulmonary Fibrosis. The objective of this paper is to analyse and compare the performance of various machine leaning models by predicting the final forced volume capacity measurements for each patient and a confidence value. It can be deployed on any computer to predict a patient's severe condition regarding lungs function which is based on a CT scan of the lungs of the patients. Lung function is checked out based on a spirometer output that measures the forced vital capacity (FVC) of the lungs. In the future, early diagnosis of pulmonary fibrosis should be possible. Machine learning model is helping to use the human resources efficiently and it is also reducing the expanses spent on the social and healthcare aspects of this deadly disease.

The preliminary design stage ensures to evaluate machine tool performances according to the simulation of reduced models. Performance criteria are defined regarding the attempted machining process requirements. In our case, we study the problem of machine tool design for hard metal cutting, where a high level of stiffness is required. In this context, this paper’s aim is to introduce a new methodology of machine tool architectures modeling, optimization, and selection with regards to their stiffness and dynamic performances at the preliminary design stage. However, this type of study requires a quantitative evaluation of performance indicators. Studied machine tool structures are modelled with simplified shape parts. The dimensions of these parts are defined as design variables. Afterward, for each considered architecture, parametric design optimization is performed to minimize its mass under the constraint of a minimal attempted stiffness all over the workspace. This approach allowed restricting the total number of machine tool architectures to be detailed further and analyzed more accurately. In a first time, the paper includes an illustration of the developed methodology through an example of machine tool architecture evaluation and optimization. In a second time, the method is used to compare different kinds of machine tool architectures regarding their ability to be light for an attempted stiffness.

Ti films are widely used in electrical engineering, biomedical instrumentation, and other industries owing to their excellent material properties. High Power Pulsed Magnetron Sputtering (HPPMS) is a promising physical vapor deposition (PVD) technique used for producing highly ionized target species, thereby opening the possibility of controlling the material properties of the growing films. Controlling the thin film properties helps achieve high quality films to cater the needs of a specific application. In this study, Ti films properties were tailored by controlling the peak and average target power values in HPPMS. The effect of peak and average target power on the plasma composition above the substrate was systematically studied. For a constant average power, the increase in the peak power significantly raises the ion-to-atom ratio and density of the plasma flux incident on the substrate. This leads to the Ti films exhibiting compressive stress, smaller grain size, and smoother surface at lower deposition rates. On the other hand, the increase in the average power at a constant peak power causes no remarkable change in the ion-to-atom ratio, but the overall magnitude of the number of metal ions and atoms and gas temperature around the substrate increase obviously. The Ti films deposited at high average powers were characterized by larger grain size with a highly preferred orientation of (002), rougher surface, and exhibited signs of tensile stress. The results obtained from this study provide guidelines for achieving high quality hard metal films with desired properties by manipulating the peak and average power in HPPMS discharge.

In order to enhance the productivity of the fine blanking process there is a tendency to apply high strength tool materials with superior resistance to wear and plastic deformation such as WC-Co hard metals. Due to the mean stress sensitivity of these high strength materials under fatigue loading conditions, there is a need to describe the tool load situation including previously unconsidered tensile tool load components and mean stress. To this end a finite element-based tool load analysis was performed that describes the cutting process and the tool's retraction from the remaining sheet material. The tool load was revealed to contain significant tensile components that occur during tool retraction. Their location on the lateral punch surface coincides with origins of tool fracture in two thirds of investigated fine blanking punches that failed close to the cutting edge in an industrial production scale fine blanking environment. The influence of friction between punch and sheet on the magnitude of the cyclic stress range and mean stress that act locally at the tool surface was investigated. As one of the main results, a first approximation for a surface quality requirement for fine blanking tools made of WC-Co hard metal was quantitatively estimated as a function of the friction coefficient based on linear elastic fracture mechanics.

Tools in injection moulding units, especially the check valves, can suffer dry hard metal - hard metal contact under severe conditions, thus experiencing increased wear. For the present study, various hard metal pairings were investigated using dry pin-on-disc tests to simulate the tribosystem of the check valve. Hard metal discs with WxC particle sizes between ~0.9 and 3 μm and binder contents between 9 and 17.5 wt. %, were tested against similar pins with smaller WxC particles. Results show that the cracking of carbides is the major wear mechanisms and that decreased WxC particles sizes together with decreased binder contents lead to lower wear rates. The combination of the hard metal with the smallest WxC particles and the lowest hardness differences between pin and disc leads in this case to a beneficial material transfer and tribolayer formation, resulting in increased wear resistance of both sliding counterparts, promising a lifetime enhancement of the check valves.

OBJECTIVE Intracranial minimally invasive procedures imply working in a restricted surgical corridor surrounded by critical structures, such as vessels and cranial nerves. Any damage to them may affect patient outcome. Neuronavigation systems may reduce the risk of such complications. In this study, the authors sought to compare standard neuronavigation (NV) and augmented reality (AR)–guided navigation with respect to the integrity of the perifocal structures during a neurosurgical approach using a novel model imitating intracranial vessels. METHODS A custom-made box, containing crisscrossing hard metal wires, a hidden nail at its bottom, and a wooden top, was scanned, fused, and referenced for the purpose of the study. The metal wires and an aneurysm clip applier were connected to a controller, which counted the number of contacts between them. Twenty-three naive participants were asked to 1) use NV to define an optimal entry point on the top, perform the smallest craniotomy possible on the wooden top, and to use a surgical microscope when placing a clip on the nail without touching the metal wires; and 2) use AR to preoperatively define an ideal trajectory, navigate the surgical microscope, and then perform the same task. The primary outcome was the number of contacts made between the metal wires and the clip applier. Secondary outcomes were craniotomy size, and trust in NV and AR to help avoid touching the metal wires, as assessed by a 9-level Likert scale. RESULTS The median number of contacts tended to be lower with the use of AR than with NV (AR, median 1 [Q1: 1, Q3: 2]; NV, median 3 [Q1: 1, Q3: 6]; p = 0.074). The size of the target-oriented craniotomy was significantly lower with the use of AR compared with NV (AR, median 4.91 cm2 [Q1: 4.71 cm2, Q3: 7.55 cm2]; and NV, median 9.62 cm2 [Q1: 7.07 cm2; Q3: 13.85 cm2]). Participants had more trust in AR than in NV (the differences posttest minus pretest were mean 0.9 [SD 1.2] and mean −0.3 [SD 0.2], respectively; p < 0.05). CONCLUSIONS The results of this study show a trend favoring the use of AR over NV with respect to reducing contact between a clip applier and the perifocal structures during a simulated clipping of an intracranial aneurysm. Target-guided craniotomies were smaller with the use of AR. AR may be used not only to localize surgical targets but also to prevent complications associated with damage to structures encountered during the surgical approach.

This study takes a new look at a number of obscure passages in the Aramaic incantation bowls and related texts discussed in Christa Müller-Kessler's article “More on puzzling words and spellings in Aramaic incantation bowls and related texts”, published inBSOAS75/1, 2012, 1–31. Among the words discussed are ברזא ‘wild boar’, מנוביא ‘wailing’, מסחיפתא ‘overthrower (type of demon)’, ספסיפא ‘burning’ and פרהזני ‘protectors’, all new to the Jewish Babylonian Aramaic lexicon, ככא ‘tusk’ and תברי “‘broken’ sounds of theshofar(as a maleficent force)”, which show new meanings for previously attested lexemes, and the new plural form שולניתא ‘maidservants’. Additional evidence for the words or expressions פגיתא ‘attack (a type of demon)’, אידיורא ‘helper’ / אידיורותא ‘help’, חי חי מץ (a divine epithet), מרוביא (a type of demon), נירבא (a hard metal) and שיפורי ‘shofars(a type of demon)’ is also adduced and a preliminary edition of the magic bowl Nippur 12 N 387 is presented.

Electro Discharge Machining (EDM) is an unconventional machining process used to make hard metal tools and complex shapes, which are difficult to machine by the conventional machining process. Additive manufacturing is the process of creating a 3D object from a CAD Model by adding one layer over another layer. In this work, it is proposed to fabricate an EDM electrode using Direct Metal Laser Sintering (DMLS) 3D printing process and compare its performance with conventional EDM electrodes in terms of Material Removal Rate (MRR), Tool Wear Rate (TWR), and surface finish. The material used for printing the EDM electrode is aluminum AlSi10 Mg and it is proposed to print it on the Direct Metal Laser Sintering 3D Printing machine. The workpiece material used for the EDM process is steel alloy 681-08 of grade D3. The experiment is conducted on EDM with the DMLS electrode and conventional electrode by varying the peak Current (I), Pulse on time (Ton), and Pulse off time (Toff). A comparison of MRR, TWR, and surface roughness is made varying the above-mentioned parameters.

Purpose: The aim of the study was to assess the exposure to Cobalt (Co) and Tungsten (W) in a group of hard metal tool sharpeners through a combined approach of air and biological monitoring, and to evaluate the effectiveness of a control and improvement intervention carried out in collaboration with the medical officers of the local Health Protection Agency, by biomonitoring. Methods: We enrolled 132 workers from 17 companies of the province of Brescia, northern Italy. The study was performed in two phases: (1) an environmental and biomonitoring survey to assess the workers’ exposure to Co and W at their usual working conditions; (2) a further biomonitoring survey 3 months after the enforcement of a control and improvement intervention, to assess its effectiveness. Results: Workers were found to be exposed to low concentration of airborne dust containing Co and W but after the intervention we recorded a significant decrease of the urinary concentrations of both Co and W. The extent of the decrease was correlated to the number of preventive industrial hygiene interventions that were carried out. Conclusions: Biological monitoring of Co and W in the hard metal tools manufacturing industry is a sensitive and effective method to evaluate the effectiveness of prevention practices.

The objective of the work was to analyze the behavior of the temperature at the tool-chip interface during the external turning process of an AISI 1045 steel with a diameter of 50 mm and a length of 200 mm using WC TNMG 16 04 12-SF hard metal insert, thus achieving the reduction of tool wear. The control parameter was the cutting speed from which the temperature was controlled indirectly. Crater and flank wear were analyzed for being regular, predictable and dominant over the life cutting tool. Also, the influence of indirect control on surface roughness behavior was studied. In order to reach this objective, the temperature behavior was initially modeled using the finite element method (MEF) and the simulation result was compared with the experimental results. Process parameter feedback was accomplished by closed loop through fuzzy control, using an ARDUINO UNO module for data acquisition. The evolution of the temperature at the chip-tool interface could thus be monitored and controlled during turning following a Fuzzy Logic control scheme.

To describe diagnostic and treatment aspects of hard metal lung disease (HMLD) and to review the current literature on the topic.This was a retrospective study based on the medical records of patients treated at the Occupational Respiratory Diseases Clinic of the Instituto do Coração, in the city of São Paulo, Brazil, between 2010 and 2013.Of 320 patients treated during the study period, 5 (1.56%) were diagnosed with HMLD. All of those 5 patients were male (mean age, 42.0 ± 13.6 years; mean duration of exposure to hard metals, 11.4 ± 8.0 years). Occupational histories were taken, after which the patients underwent clinical evaluation, chest HRCT, pulmonary function tests, bronchoscopy, BAL, and lung biopsy. Restrictive lung disease was found in all subjects. The most common chest HRCT finding was ground glass opacities (in 80%). In 4 patients, BALF revealed multinucleated giant cells. In 3 patients, lung biopsy revealed giant cell interstitial pneumonia. One patient was diagnosed with desquamative interstitial pneumonia associated with cellular bronchiolitis, and another was diagnosed with a hypersensitivity pneumonitis pattern. All patients were withdrawn from exposure and treated with corticosteroid. Clinical improvement occurred in 2 patients, whereas the disease progressed in 3.Although HMLD is a rare entity, it should always be included in the differential diagnosis of respiratory dysfunction in workers with a high occupational risk of exposure to hard metal particles. A relevant history (clinical and occupational) accompanied by chest HRCT and BAL findings suggestive of the disease might be sufficient for the diagnosis.Descrever aspectos relacionados ao diagnóstico e tratamento de pacientes com doença pulmonar por metal duro (DPMD) e realizar uma revisão da literatura.Estudo retrospectivo dos prontuários médicos de pacientes atendidos no Serviço de Doenças Respiratórias Ocupacionais do Instituto do Coração, localizado na cidade de São Paulo, entre 2010 e 2013.Entre 320 pacientes atendidos no período do estudo, 5 (1,56%) foram diagnosticados com DPMD. Todos os pacientes eram do sexo masculino, com média de idade de 42,0 ± 13,6 anos e média de tempo de exposição a metal duro de 11,4 ± 8,0 anos. Os pacientes foram submetidos a avaliação clinica, história ocupacional, TCAR de tórax, prova de função pulmonar, broncoscopia com LBA e biópsia pulmonar. Todos apresentaram distúrbio ventilatório restritivo. O achado de imagem à TCAR de tórax mais frequente foi de opacidades em vidro fosco (em 80%). Em 4 pacientes, o LBA revelou presença de células gigantes multinucleadas. Em 3, foi diagnosticada pneumonia intersticial por células gigantes na biópsia pulmonar. Houve o diagnóstico de pneumonia intersticial descamativa associada à bronquiolite celular em 1 paciente e de pneumonite de hipersensibilidade em 1. Todos foram afastados da exposição e tratados com corticoide. Houve melhora em 2 pacientes e progressão da doença em 3.Apesar de ser uma entidade rara, a DPMD deve ser sempre considerada em trabalhadores com risco ocupacional elevado de exposição a metais duros. A história clínica e ocupacional associada a achados em TCAR de tórax e LBA sugestivos da doença podem ser suficientes para o diagnóstico.

Tungsten and its alloys find critical applications in several important sectors, such as defence, aerospace, mining, manufacturing, telecommunications etc., which are key to economic development and national security. Global tungsten deposits are limited (~3.3 million tonnes) and highly localized; China dominates the supply with more than 84% share. India doesn’t have any economic tungsten ore deposits, and produces meagre quantities of tungsten in comparison to its demand of ~1500 tonne/year. In order to lessen the import burden and supply risk to the country’s defence programmes, India is required to focus on producing this important metal from various available secondary and lean grade resources such as scraps and tailings. This article presents some of the recently developed and commercialized tungsten recycling technologies by CSIR-NML, which include: (1) recycling of tungsten carbide (WC) hard metal scraps for production of high pure yellow tungsten oxide (WO3) and W-metal powder; and (2) production of high pure sodium tungstate (Na2WO4·2H2O) from spent hydro-refining catalysts. Besides describing the process flow-sheets and product specifications, the paper highlights the advantages of CSIR-NML technologies over the presently practiced technologies.

Electrical discharge machining (EDM) or micro EDM found successful for production of micro holes on ceramics, hard metal and alloys. In the present study, experimental investigation and parametric optimization are carried out on EDM process for producing micro holes of diameter 500 µm on stainless steel (grade 304).Current (I), gap voltage (V) and pulse on time (T on) are considered as process parameters and are optimized for improving hole quality [i.e., overcut (OC) and taper angle (θ)]. Statistical regression models are developed for predicting OC and θ and effects of parameters are studied using surface plots. The optimal parameters are obtained for single as well as multiple performance characteristics. The traditional Taguchi analysis is used for optimization of each objective individually. This work presents the application of Taguchi optimization for simultaneous minimization of over cut (OC) and taper angle (θ) for improvement of hole quality in drilling micro holes. The optimal level of factors based on analysis of means (ANOM) with highest signal to noise (S/N) ratio is found as (i.e., I1 − V3 − T on2). This corresponds to parametric combination being 10 A, 50 V and 150 µs for I, V and T on respectively that produce improved hole quality with minimum overcut and taper angle. The obtained result is compared with desirability analysis and found that it is closer.

Statement of problem Marginal and axial discrepancies of metal ceramic restorations are key to their long-term success. Little information is available for metal ceramic restorations fabricated with soft metal milling and laser sintering technologies. Purpose The purpose of this in vitro study was to compare the marginal, axial, and occlusal discrepancies in single-unit metal ceramic restorations fabricated with new production techniques with those in a single-unit restoration fabricated using a conventional technique. Material and methods After the artificial tooth was prepared, impressions were made, and 40 dies were obtained. Dies were randomly divided into 4 groups (n=10). Cobalt-chromium (Co-Cr) cast (C), hard metal milled (HM), laser sintered (LS), and soft metal milled (SM) copings were fabricated. Marginal, axial, and occlusal discrepancies of these copings were measured using the silicone replica technique before and after the application of veneering ceramic. Data were analyzed with repeated measurements 2-way ANOVAs and Bonferroni post hoc tests (?=.05). Results Significant differences were found in the increase of marginal discrepancy after the application of veneering ceramic in the LS group (P=.016). However, no significant differences in marginal discrepancy were found whether veneering ceramic was applied to copings before or after in the other groups (P>.05). With regard to marginal and occlusal discrepancies, significant differences were found among the production techniques (P.05). Conclusion This in vitro study showed that metal ceramic restorations produced with HM and newly introduced SM techniques exhibited better marginal adaptations than those produced with the LS or C technique. © 2016 Editorial Council for the Journal of Prosthetic Dentistry

This article explains the physical features of various methods of compaction, primarily for end of life vehicle (ELV) bodies coming from ELV processors. By EU directive 2000/53/EC it is mandatory for all EU members to meet the reuse of 95 % of the old vehicle weight. It means that the vehicles have to be decomposed completely – metal shells freed from all the components like interior trim, rubber sealing, glass, all the liquids, seats tanks and other hard metal components like drive-train, engine etc. It follows that pressing machines used for compressing whole vehicles today, are overpowered, with high energy demand, robust structures and heavy weight. Hence it makes sense to concentrate on comparison of pressing methods and choosing the most energy efficient one and the designing a new device, if necessary. This device is aimed for operation in Slovak Republic but also usable in other countries with same or similar requirements such as optimized system for processing of car bodies, mobile concept and modularity of the whole mobile modular disintegration complex consisting of a pressing machine, shears and shredder. Car body structure

The wind tunnel model, balance and sting are exposed to the large transient load in the blowdown wind tunnels. As part of the research, in order to improve wind tunnel testing, a new high stiffness sting for testing in the T-38 wind tunnel is developed. The existing steel sting, with modular construction, has been used for initial analysis. Its central cylindrical part is changed with core made of material of the high modulus of the elasticity. In this way geometrically the same sting is obtained, but stiffness of the sting is increased. Comparison between elastic characteristics of the combined sting and steel sting is made on the basis of the results obtained by load simulation and experimental verification. Load simulation results are obtained using NX Nastran software. Results of the experimental verification of the new sting are obtained in the T-38 wind tunnel test.

Cermets are a category of materials including ceramic and metallic phases, which possess the combined properties of both phases. Over the last few decades, numerous conventional processes such as powder metallurgy techinques and casting have been proposed for the fabrication of cermet components. In recent years, additive manufacturing (AM) has emerged as a promising method that can eliminate most of the limitations of conventional production methods. Among AM processes, selective laser sintering/melting (SLS/SLM), laser engineering net shaping (LENS), direct laser fabrication (DLF), binder jet 3D printing, and 3D gel/direct-ink-write/robocasting printing have been investigated for manufacturing bulk cermet parts. This study presents a summary of research that has been conducted to produce bulk cermets by additive manufacturing. / © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/BY/4.0/).

Hard metal lung disease (HMLD) is a pneumoconiosis caused by occupational exposure to hard metals such as tungsten carbide and cobalt, but the treatment strategies for HMLD have not been well established. A 68-year-old Japanese man with occupational history as a grinder of hard metals for 18 years referred to our hospital because of dry cough and dyspnea. A chest computed tomography (CT) on admission revealed centrilobular micronodules, ground-glass opacities, and reticular opacities in the peripheral zone of both lungs. Mineralogic analyses of lung tissues detected components of hard metals, such as tungsten, titanium and iron, and the same metals were also detected in the sample of the dust of his workplace. Thus, the patient was diagnosed as having HMLD based on occupational exposure history and radiologic and mineralogic analyses of the lung. Corticosteroid therapy was initiated, which resulted in partial improvements in his symptoms, radiological and pulmonary functional findings. In a review of the 18 case reports of HMLD treated with corticosteroids, including our case, the majority of patients (77.8%) showed favorable responses to corticosteroid treatment. Furthermore, the presence of fibrotic changes, such as reticular opacity, in radiological examinations was associated with the resistance to corticosteroids. In conclusion, the majority of patients with HMLD are expected to favorable response to corticosteroid treatment, whereas chest CT findings such as fibrotic changes may be predictive of the resistance of corticosteroid treatment. Lastly, proper prevention of hard metal exposure is most important as the first step.

Introduction Republic of Turkey Social Security Institution (SSI) is the institution responsible for statistics of occupational diseases in Turkey by law. We aimed to evaluate proportion of pneumoconiosis in occupational diseases and occupational pulmonary diseases in annual statistics reports of SSI. Methods Annual statistics reports published between 2006–2015 by SSI were evaluated. Diagnoses classified as pneumoconiosis in reports published before 2013 were coal worker’s pneumoconiosis, asbestos or other mineral fibre induced pneumoconiosis, talcosis, silicosis, aluminosis, boxide fibrosis, beriliosis, graphite fibrosis, siderosis, stannosis, and other unclassified pneumoconiosis. Diagnoses classified as pneumoconiosis in reports published starting from 2013 were silicosis and silicotuberculosis, asbestosis, silicatosis, siderosis, and pneumoconiosis induced by hard metal dusts, aluminium, and its compounds. Result Total numbers of cases with occupational diseases varied between 351 and 1208 in annual reports of SSI. Most frequent occupational diseases were pneumoconiosis and diseases induced by lead and its dusts. When occupational diseases listed according to the frequency, rank of pneumoconiosis was 1 or 2 in all of the evaluated years. Total numbers of cases with pneumoconiosis varied between 68–1010. Percentage of pneumoconiosis in all cases with occupational diseases and in cases with occupational pulmonary diseases varied between 19.3%–83.6% and 80.2%–99.3% respectively. Discussion Despite low total numbers of occupational diseases in the annual SSI statistics, pneumoconiosis constitutes the major proportion of occupational diseases in Turkey. This could be a result of directive about dust induced diseases which defines periodical health surveillance for workers with high-risk occupations. Proper application of initial assessment of fitness and health surveillance for workers with current or prior history of risk of pneumoconiosis may increase diagnoses.

ObjectivesCobalt (Co) exposure is associated with adverse health effects including skin sensitisation, asthma and interstitial lung fibrosis. Exposure to Co in industrial settings is often assessed using air samples or biomonitoring in urine. Skin exposure is rarely measured. Aim of this study was to quantify and compare the importance of Co skin exposure and respiratory exposure in determining urinary Co concentrations.MethodsCo skin exposure was measured in 76 hard metal workers by acid wipe sampling before and at the end of work shifts. Spot urine was collected during a 24-hour period from the start of a shift. Respiratory exposure was measured by personal inhalable dust sampling during a shift in 30 workers. Co was analysed by inductively coupled plasma mass spectrometry.ResultsQuantile regression modelling showed that a doubling of Co on skin before or at the end of shift increased the median urinary concentration of Co by 70% (pConclusionsThe results indicate an association between Co skin exposure and urinary Co concentrations. This should be considered when using urinary Co as a biomarker of exposure.

Machining is a complicated process where many variables can directly affect the desired results. Among them, tool vibration is the most critical phenomenon which affects the life of the cutting tool, quality of the components machined and functional behavior of the machined tools. This tool vibration can be controlled by increasing the rigidity of the cutting tool through damper. The present investigation aims at suppressing tool vibration during end milling process using magnetorheological fluid damper which acts as a viscoelastic spring with non-linear vibration characteristics. Magnetorheological fluid damper along with fixtures was designed and fabricated according to the required size. Cutting experiments were conducted to arrive at set of compositional parameters that can reduce tool vibration and hence promote better cutting performance during end milling of AISI 4340 steel of 45 HRC using hard metal insert with sculptured rake face. From the results, it was observed that the use of magnetorheological fluid damper reduces tool vibration and improves cutting performance effectively.

In boring process due to larger overhanging length of tool holder, tool vibration is considered as a significant factor which results in poor surface finish, noise generation, accelerated tool wear and reduced life period of machine tool. This tool vibration is a result of interaction between metal cutting process and the dynamics of machine tool. In order to reduce tool vibration it is necessary to develop suitable mechanisms which will in-turn increase the productivity in manufacturing industries. This investigation aims at analyzing the tool holder with impact damper on tool vibration during boring of hardened AISI4340 steel using hard metal insert with sculptured rake face. Impact damper used in this study consists of a concentrated mass of predetermined size and shape mounted on the tool shank at a specific location by means of springs. Material of impact damper and the location of the damper on the tool shank for achieving effective damping was determined by using computational analysis. When the damper was mounted on the tool shank, its vibration characteristics got altered and provided an inherent damping capability to the tool holder by suppressing tool vibration. Experimental work was carried out to study the influence of impact damper on tool vibration and cutting performance. From both computational and experimental results, it was observed that tool vibration was reduced effectively when impact damper was embedded with tool holder.

Plasma focus (PF) technique is potentially promising candidate for the materials processing and surface modification because of the radiations in a wide range of energies. In this review paper, we discuss and report the use of PF device for transition hard metal nitrides thin film synthesis and investigation of some effective deposition parameters in PF. In this paper, we focus on tungsten nitride film, which has promising industrial and scientific applications. A systematic study has been performed to investigate the effect of the number of focus shots and substrate axial and angular positions on the physical properties of tungsten nitride film deposited by PF device. It is indicated that these parameters are effective in order to obtain good quality tungsten nitride film and estimating the optimum conditions for growing these films with desired physical properties.

Occupational and environmental lung disease remains a major cause of respiratory impairment worldwide. Despite regulations, increasing rates of coal worker's pneumoconiosis and progressive massive fibrosis are being reported in the United States. Dust exposures are occurring in new industries, for instance, silica in hydraulic fracking. Nonoccupational environmental lung disease contributes to major respiratory disease, asthma, and COPD. Knowledge of the imaging patterns of occupational and environmental lung disease is critical in diagnosing patients with occult exposures and managing patients with suspected or known exposures.

Penile strangulation by metal ring is a rare urological emergency situation which requires urgent decompression of the penis to avoid adverse effect. It is usually associated with an attempt to improve sexual act and/or to prolong erection. But sometimes, cutting of the ring to decompress the penis safely is a very difficult task particularly when the strangulating object is a hard metal object as in our case. Here, we present a case which was managed by cutting in a novel way with the help of dental micromotor with wheel shape bur.

Inhalation of cobalt salts in the ‘hard metal’ industry has been shown to cause giant cell interstitial pneumonitis. Substantial ingestion of cobalt salts can produce neuro-ocular, cardiac and/or thyroid toxicity. Systemic cobalt toxicity has been encountered occasionally in recipients of cobalt-containing hip prostheses. Ingestion of copper salts causes a corrosive gastroenteritis. Chronic inhalation of copper-containing pesticides has caused pulmonary fibrosis. Lead can be absorbed following inhalation or ingestion and is toxic to most organ systems through mechanisms that involve complexing with important functional chemical groups or substitution of essential metal ions. Management involves avoidance of exposure and, in more severe cases, chelation therapy with either sodium calcium edetate or dimercaptosuccinic acid (DMSA). The central nervous system is the most susceptible target organ for mercury. Chelation therapy with 2,3-dimercapto-1-propanesulfonic acid (DMPS) can enhance mercury elimination.

Cobalt is a metal with a silvery appearance with special properties such as ferromagnetism and a high resistance to heat and wear, causing it to be widely used in many different applications. Cobalt has a well-known toxicity, and it is a potent skin sensitizer and one of the most common causes of contact allergy. Cobalt allergy is common in dermatitis patients in general, but more pronounced among specific occupational groups. Among patch-tested dermatitis patients, prevalence numbers range from 4.5% to around 11% for studies from Europe and North America, whereas the typical range for occupational groups are 4% to 20%. Some of the most well-known occupations where cobalt allergy have been prevalent include hard metal workers, pottery and porcelain workers, and construction workers. Consumer exposure to cobalt mainly occurs from items such as jeweller, leather, cosmetics and electronics. In jewellery and electronics cobalt is used in its metallic state, but for leather and cosmetics it is mostly used as a pigment.

Hard metal castings are widely used in the coal mill pulverizer as construction material for coal crushers. During its operation crushers and mills experience degradation caused by abrasion load. This research dealed with the surface overlaying of similiar material on the surface of white cast iron by mean of gravity casting. The die blank casting was preheated prior to the casting process of outer layer made of Ni-Hard white cast iron to guarantee bonding processes and avoid any crack. The preheating temperature of die blankin ther range of 500C up to 850C was set up to reach the interface temperature in the range of 887°C -1198°C and the flushing time was varied between 10-20 seconds. Studies carried on the microstructure of sample material revealed a formation of metallurgical bonding at the preheating temperature above 625 °C by pouring temperature ranging from 1438 °C to 1468 °C. Metallographical and chemical composition by mean of EDS examination were performed to observed the resut. This research c...

Giant cell interstitial pneumonia (GIP) is a rare form of chronic interstitial pneumonia typically associated with hard metal exposure. Only two cases of GIP induced by nitrofurantoin have been reported in the medical literature. We are reporting a case of recurrent nitrofurantoin-induced GIP. Although extremely rare, GIP needs to be included in the differential diagnosis in patients with chronic nitrofurantoin use who present with respiratory illness.

One of the most important things for a milling is know which material would to be machined. Different milling conditions are required for each type of material and it is not possible to use just one type of milling tool if we want to have the best efficiency. Therefore different setting of tool geometry is used for different materials. In end mills change of rake angle has an effect on plastic deformation, chip making and forces from machining. For changing surface quality, friction and toughness of mill, we must change the clearance angle on the tool. The next angle, which we can find, on the tool is the edge angle and it is given by the previous two angles. The helix angle, which sets which direction the chip goes out, depends on vibration or the number of edges, which will be in the cut. Three end milling variations, which have different degrees of geometry change, were suggested. They are based on current end mill from hard metal. More information and results are available in the article.

Replacement of electrolytic hard chromium (EHC) method by Thermal Spray Technology has shown a growing interest the past decades, mainly pioneered by depositing WC-based material by conventional HVOF processes. Lower thermal energy and higher kinetic energy of sprayed particles achieved by newly-developed supersonic air fuel system, so-called HVAF-M3, significantly reduce decarburization, and increase wear and corrosion resistance properties, making HVAF-sprayed coatings attractive both economically and environmentally. In the present work, a first order process map has been intended via a full factorial design of experiments (DoE) to establish relationships between powder feedstock characteristics, such as primary carbides grain size, binder grain size and powder strength, and coating microstructure and mechanical properties. A second order process map was then established to study possible correlations between the deposit microstructural properties and their respective abrasion/erosion wear and corrosion performances.