The Experts below are selected from a list of 546 Experts worldwide ranked by ideXlab platform
Osman Gencel - One of the best experts on this subject based on the ideXlab platform.
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Neutron Radiation Tests about FeCr Slag and Natural Zeolite Loaded Brick Samples
Science and Technology of Nuclear Installations, 2014Co-Authors: Vedat Veli Cay, Osman Gencel, Mucahit Sutcu, Turgay KorkutAbstract:Neutron shielding performances of new brick samples are investigated. Brick samples including 10, 20, and 30 percentages of Ferrochromium slag (FeCr waste) and natural zeolite are prepared and mechanical properties are obtained. Total macroscopic cross sections are calculated by using results of 4.5 MeV neutron transmission experiments. As a result, neutron shielding capacity of brick samples increases with increasing FeCr slag and natural zeolite percentages. This information could be useful in the area of neutron shielding.
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properties of bricks with waste Ferrochromium slag and zeolite
Journal of Cleaner Production, 2013Co-Authors: Osman Gencel, Vedat Veli Cay, Mucahit Sutcu, Ertugrul Erdogmus, Vahdettin Koc, Mustafa Sabri GokAbstract:Effect of Ferrochromium slag, zeolite and combinations on physical, mechanical, thermal conductivity and microstructure properties of bricks was investigated. They were substituted to brick raw material. Semi-dry mixtures were compressed with 20 MPa. Samples were fired at rate of 5 °C/min until 900 °C for 2 h. Characterization of fired bricks, density, porosity, water absorption, weight loss, compressive and bending strength, thermal conductivity properties and microstructural and phase analysis of bricks were determined. Mechanical strengths of bricks were higher than 7 MPa. Thermal conductivity of samples decreases 42.3%. Results showed that bricks with zeolite and slag could be used as construction material.
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x ray gamma and neutron radiation tests on epoxy Ferrochromium slag composites by experiments and monte carlo simulations
International Journal of Polymer Analysis and Characterization, 2013Co-Authors: Turgay Korkut, Osman Gencel, Erol Kam, Witold BrostowAbstract:Radiation shielding effects of Ferrochromium slag loading hardened epoxy resin samples were investigated. Five different samples including different percentages of epoxy resin and Ferrochromium slag were produced. X-ray, gamma ray, and neutron particle transmission experiments were performed for epoxy-Ferrochromium slag composites. Also, FLUKA Monte Carlo simulations were made to obtain absorbed doses. As a result, radiation shielding performance increases with increasing Ferrochromium slag additive in epoxy.
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combined effects of fly ash and waste Ferrochromium on properties of concrete
Construction and Building Materials, 2012Co-Authors: Osman Gencel, Fuat Koksal, Cengiz Ozel, Witold BrostowAbstract:Abstract Cement and water-to-binder ratio were kept constant as 400 kg/m 3 and 0.40, respectively. Cement was replaced with fly ash at the ratio of 10, 20 and 30 wt.%. Coarse limestone aggregates were replaced with coarse Ferrochromium aggregate at the ratio of 25, 50 and 75 wt.%. On fresh concretes, slump, air content and unit weight tests were performed. On the hardened concretes, compressive strength, splitting tensile strength, elasticity modulus, abrasion resistance, freeze–thaw resistance, porosity and water absorption were determined. The use of fly ash lowers values several properties: compressive strength, splitting tensile strength, elasticity modulus and wear resistance; however freeze–thaw durability increases. Usage of Ferrochromium aggregates increases strength of concrete and also abrasive wear resistance. Effect of Ferrochromium aggregates on porosity and water absorption of concrete is insignificant while fly ash enhances these properties. A highly accurate equation relating compressive strength to splitting tensile strength is provided. An equation relating wear to compressive strength and fly ash volume fraction is also defined.
Mei Zhang - One of the best experts on this subject based on the ideXlab platform.
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crystallization kinetics of glass ceramics prepared from high carbon Ferrochromium slag
Ceramics International, 2016Co-Authors: Zhitao Bai, Guibo Qiu, Changsheng Yue, Min Guo, Mei ZhangAbstract:Abstract Glass-ceramics were successfully prepared from high-carbon Ferrochromium slag (HCFS), and the optimum heat-treatment conditions were determined by analysis of the crystallization kinetics. The parent glass is first prepared in five different ratios of HCFS to waste glass (R(H/W)), then heat-treated separately at five heating rates (α) and monitored by DSC. As the value of R(H/W) increases from 0.60 to 1.67, the crystallization activation energy (E c ) decreases from 253.41 to 183.52 kJ/mol. The nucleation and crystallization temperatures decrease from 641.7 to 612.2 °C, and 822.8–814.7 °C, respectively, and both are lower than that of ordinary metallurgy slag. These results indicate that using HCFS to produce glass-ceramics both facilitates its production and saves energy. The crystallization index (n) increases with increasing R(H/W), and when n exceeds 2.32, all of the parent glass samples with different R(H/W) crystallize as bulk crystallization. The crystallization index (n) increases as the heating rate α decreases from 25 to 5 °C/min, with a maximum value of n (5.94) observed when α is 5 °C/min. These conditions produce the largest aspect ratio and highest density of the crystal grain in the glass-ceramics. Our results show the optimal HCFS-based glass-ceramics were obtained with a R(H/W) of 1.29 and a 5 °C/min heating rate; under those conditions, the parent glass nucleates and crystalizes at 627.1 and 820.9 °C, respectively.
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synthesis and characterization of glass ceramics prepared from high carbon Ferrochromium slag
RSC Advances, 2016Co-Authors: Zhitao Bai, Guibo Qiu, Min Guo, Ben Peng, Mei ZhangAbstract:Glass-ceramics have been successfully prepared from high-carbon Ferrochromium slag (HCFS) and waste glass (WG), and the microstructural characterization and mechanical properties of the glass-ceramics were subsequently investigated. The development of HCFS-based glass-ceramics involves the nucleation and crystallization stages from the parent glass. With the increase in mass ratio of HCFS and WG (R(H/W)) from 0.60 to 1.67, the number of bridging oxygens of Si in the parent glass is reduced, as shown via Raman spectroscopy. Thus, their degree of polymerization decreases with it, and the temperature of nucleation and crystallization increase, which is consistent with the DSC results. The SEM images and EDS results indicate that the increasing value of R(H/W) decreases the crystal grain size and consequently increases the microhardness of the glass-ceramics. But the porosity simultaneously increases, which makes the bending strength increase at first and subsequently decrease. And the optimum properties of HCFS-based glass-ceramic samples in the present work are obtained when R(H/W) reaches 1.29, that is, a bending strength of 104 MPa and a microhardness of 9860 MPa.
Witold Brostow - One of the best experts on this subject based on the ideXlab platform.
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x ray gamma and neutron radiation tests on epoxy Ferrochromium slag composites by experiments and monte carlo simulations
International Journal of Polymer Analysis and Characterization, 2013Co-Authors: Turgay Korkut, Osman Gencel, Erol Kam, Witold BrostowAbstract:Radiation shielding effects of Ferrochromium slag loading hardened epoxy resin samples were investigated. Five different samples including different percentages of epoxy resin and Ferrochromium slag were produced. X-ray, gamma ray, and neutron particle transmission experiments were performed for epoxy-Ferrochromium slag composites. Also, FLUKA Monte Carlo simulations were made to obtain absorbed doses. As a result, radiation shielding performance increases with increasing Ferrochromium slag additive in epoxy.
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combined effects of fly ash and waste Ferrochromium on properties of concrete
Construction and Building Materials, 2012Co-Authors: Osman Gencel, Fuat Koksal, Cengiz Ozel, Witold BrostowAbstract:Abstract Cement and water-to-binder ratio were kept constant as 400 kg/m 3 and 0.40, respectively. Cement was replaced with fly ash at the ratio of 10, 20 and 30 wt.%. Coarse limestone aggregates were replaced with coarse Ferrochromium aggregate at the ratio of 25, 50 and 75 wt.%. On fresh concretes, slump, air content and unit weight tests were performed. On the hardened concretes, compressive strength, splitting tensile strength, elasticity modulus, abrasion resistance, freeze–thaw resistance, porosity and water absorption were determined. The use of fly ash lowers values several properties: compressive strength, splitting tensile strength, elasticity modulus and wear resistance; however freeze–thaw durability increases. Usage of Ferrochromium aggregates increases strength of concrete and also abrasive wear resistance. Effect of Ferrochromium aggregates on porosity and water absorption of concrete is insignificant while fly ash enhances these properties. A highly accurate equation relating compressive strength to splitting tensile strength is provided. An equation relating wear to compressive strength and fly ash volume fraction is also defined.
Eero Pukkala - One of the best experts on this subject based on the ideXlab platform.
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cause specific mortality in finnish Ferrochromium and stainless steel production workers
Occupational Medicine, 2016Co-Authors: Markku Huvinen, Eero PukkalaAbstract:Methods W e studied Finnish stainless steel production chain workers employed between 1967 and 2004, from chromite mining to cold rolling of stainless steel, divided into sub-cohorts by production units with specific exposure patterns. We obtained causes of death for the years 1971–2012 from Statistics Finland. We calculated standardized mortality ratios (SMRs) as ratios of observed and expected numbers of deaths based on population mortality rates of the same region. Results Among 8088 w orkers studied, overall mortality was significantly decreased (SMR 0.77; 95% confidence interval [CI] 0.70–0.84), largely due to low mortality from diseases of the circulatory system (SMR 0.71; 95% CI 0.61–0.81). In chromite mine, stainless steel melting shop and metallurgical laboratory workers, the SMR for circulatory disease was below 0.4 (SMR 0.33; 95% CI 0.07–0.95, SMR 0.22; 95% CI 0.05–0.65 and SMR 0.16; 95% CI 0.00–0.90, respectively). Mortality from accidents (SMR 0.84; 95% CI 0.67–1.04) and suicides (SMR 0.72; 95% CI 0.56–0.91) was also lower than in the reference population. Conclusions W orking in the Finnish Ferrochromium and stainless steel industry appears not to be associated with increased mortality.
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cancer incidence among finnish Ferrochromium and stainless steel production workers in 1967 2011 a cohort study
BMJ Open, 2013Co-Authors: Markku Huvinen, Eero PukkalaAbstract:Objectives The aim of the study was to assess the risk of cancer among workers employed in the Finnish Ferrochromium and stainless steel industry since the beginning of production in 1967. Methods The study cohort was made up of all persons employed by the Finnish stainless steel production chain from chromite mining to cold rolling of stainless steel during the period 1967–2004, and it was divided into subcohorts by production units with specific exposure patterns of the subcohorts assessed in previous studies. Follow-up for cancer through the files of the Finnish Cancer Registry was performed using the personal identity code as key. Standardised incidence ratios (SIRs) were calculated as the ratios of observed numbers of cancer cases and numbers expected on the basis of incidence rates in the population of the same region. Results The overall cancer incidence was at the expected level. The lung cancer risk was decreased in the whole cohort (SIR 0.79; 95% CI 0.65 to 1.08). The incidence of prostate cancer was significantly increased (1.31; 1.05 to 1.61) and that for kidney cancer was significantly decreased (0.38; 0.14 to 0.82). None of the department-specific SIRs for lung cancer were significantly different from 1.0. No cancers of the nose and nasal sinuses were observed among workers in the Ferrochromium smelter or the stainless steel melting shop. Conclusions It is not likely that the occupational exposures in the Finnish Ferrochromium and stainless steel industry would have increased the risk of cancer.
Mustafa Sabri Gok - One of the best experts on this subject based on the ideXlab platform.
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Investigation of Abrasive Wear Behavior of Industrial Wastes on Al 6061 Material Using Rubber Wheel Abrasion Test (RWAT) Method
Kaunas University of Technology, 2019Co-Authors: Mustafa Sabri Gok, Hanife OzlimaAbstract:In this study, the abrading characteristics of the slags, generated in the form of industrial waste during raw iron, steel and Ferrochromium ore production, are investigated. Granulated blast furnace slag (GBFS), basic oxygen furnace slag (BOF) Ferrochromium slag (FCS) and commercial Al2O3 powder were used during the tests. Abrasion tests were conducted using Rubber Wheel Abrasion Wear (RWAT) method. Al 6061 was chosen as the counter body material. The tests were conducted under 25, 50, 75 and 100 N loads with 100 r/min rubber wheel rotational speed. The highest rate of abrasion was obtained from GBFS under all loads as a result of the conducted tests. Under high loads, the abrading performance of FCS reached that of the commercial Al2O3 powder. BOF was found to have no abrading capability. Surface morphology and SPQ (spike parameter-quadratic fit) value were as effective as the particle hardness in the evaluation of abrading performance. As dominant wear mechanisms, spalling, ploughing and micro-scratch formation were observed on the specimens abraded with GBFS and Al2O3, whereas severe plastic deformation-induced extrusion was observed on the specimen abraded with FCS.
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Ferrochromium slag as a protective coating material against oxidation for caster rolls
International Journal of Applied Ceramic Technology, 2018Co-Authors: Yilmaz Kucuk, Mustafa Sabri Gok, Mecit Oge, Abdullah Cahit KaraoglanliAbstract:In this study, Ferrochromium (FeCr) slag, which is available as an industrial waste, is proposed as a protective surface coating material particularly for protection of continuous casting rolls against oxidation. FeCr slag was successfully deposited with atmospheric plasma spray (APS) method. Before the coating process, FeCr slag powder prepared in the particle size range of 5-38 μm, was investigated using conventional characterization methods (XRD, SEM, TGA etc.). Thermal Barrier Coating (TBC) system was used as a basis for deposition processes. Accordingly, NiCoCrAlY (Amdry, −45 + 5 μm) was firstly deposited as metallic bond coat layer onto the surface of AISI 420 substrate, and then FeCr slag layer was deposited as the top coating layer. After the deposition of FeCr slag powder, the resulting coating layer was found to have low porosity with a homogeneous microstructure. The deposited FeCr slag coatings were subjected to isothermal oxidation tests at different temperatures and test durations for determination of their oxidation behavior and upper operating temperature limits. The results obtained from this study indicate that FeCr slag can be considered as an alternative protective coating material for caster rolls which are subjected to high temperatures up to 800°C.
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properties of bricks with waste Ferrochromium slag and zeolite
Journal of Cleaner Production, 2013Co-Authors: Osman Gencel, Vedat Veli Cay, Mucahit Sutcu, Ertugrul Erdogmus, Vahdettin Koc, Mustafa Sabri GokAbstract:Effect of Ferrochromium slag, zeolite and combinations on physical, mechanical, thermal conductivity and microstructure properties of bricks was investigated. They were substituted to brick raw material. Semi-dry mixtures were compressed with 20 MPa. Samples were fired at rate of 5 °C/min until 900 °C for 2 h. Characterization of fired bricks, density, porosity, water absorption, weight loss, compressive and bending strength, thermal conductivity properties and microstructural and phase analysis of bricks were determined. Mechanical strengths of bricks were higher than 7 MPa. Thermal conductivity of samples decreases 42.3%. Results showed that bricks with zeolite and slag could be used as construction material.