Iron Inclusions Research Articles

High-Temperature Drive Shaft Failure with a Twist

An unusual high-temperature failure is presented involving the bearings and drive shaft of a centrifugal slurry pump. The unique characteristics of the failure are explored including localized heating and interactions between the ductile iron bearing collar and the shaft material. Maximum surface temperature of the shaft at the time of failure is estimated to be 2100–2300 °F. Partial melting of the ductile iron bearing collar and softening of the shaft appears to have resulted in both the inclusion of ductile iron in the shaft material in the molten state and a form of friction stir welding which joined the two components. Hardness values in excess of 900 Vickers were recorded around the material interface. It is theorized that rapid diffusion of carbon into the shaft material occurred during failure facilitated by mechanical mixing due to severe high-temperature deformation. Graphite nodularity and phase analysis of the ductile iron collar and an embedded ductile iron fragment were conducted by means of microscopy and image analysis.

Compromised zinc status of experimental rats as a consequence of prolonged iron & calcium supplementation.

Background & objectives:Iron supplementation is usually given to pregnant and lactating women who may also have marginal deficiency of zinc. The negative impact of supplemental iron and calcium on zinc status is a cause of concern. The present investigation was undertaken to examine the effect of inclusion of iron and calcium in the diet at supplementary levels on zinc status of experimental rats.Methods:Groups of experimental rats were maintained on diets supplemented with iron (Molar ratio - Zn:Fe 1:30) and calcium (Molar ratio - Zn:Ca 1:667) both individually and in combination for six weeks. Zinc status of these rats was assessed by determining zinc concentration in circulation and in organs, and the activities of zinc containing enzymes in serum and liver.Results:The zinc status of experimental rats receiving supplemental levels of iron and calcium was significantly compromised. Zinc concentration in serum, kidney, spleen and liver was reduced significantly by both these minerals. Six weeks of supplementation of iron and calcium individually, significantly reduced the activity of liver and serum superoxide dismutase and alkaline phosphatase. Activity of liver alcohol dehydrogenase was lowered in calcium supplemented group and in calcium + iron supplemented group, while that of carbonic anhydrase was significantly reduced by iron, calcium and their combination.Interpretation & conclusions:Supplemental levels of iron and calcium, both individually and in combination, significantly compromised the zinc status of experimental rats. This negative effect of these two minerals was more prominent when these were supplemented for a period of six weeks.

Feedback magnetization of ultra-low index irradiative structure

Ultra-low refractive index irradiative structure is considered. The structure consists of a patch antenna with the metamaterial slab located on top of the antenna, as superstrate. In this study, ultra-low index phenomenon of the irradiative system is associated with improving the directivity of the patch antenna by putting the metamaterial slab on top of the antenna. The last phenomenon, in turn, is associated with the feedback partial magnetization of Iron inclusions of the slab caused by the radiation from the antenna. Mathematical model for evaluating the complex effective relative permittivity of the irradiative structure is developed. Numerical calculations for complex effective relative permittivity of the irradiative structure and real part of the complex effective relative permeability of the metamaterial slab are done in the study.

Herbicide-Impacted Sediment Remediation. I: Delineation and Treatability Study

This paper is the first in a series on the Tyco Fire Products LP Sediment Removal Project (Marinette, Wisconsin) describing the dredging, stabilization and solidification (S/S) treatment, and nonhazardous disposal of arsenic-impacted sediments. Arsenic (As) impacts were associated primarily with the release of monomethyl arsonic acid (MMA) [CH3AsO(OH)2] and dimethyl arsinic acid (DMA) [(CH3)2AsO(OH)] derived from historic herbicide manufacturing and storage activities. Two main sediment horizons were affected: an upper soft sediment [soft dredged material (DM)] and an underlying semiconsolidated material (SCM) layer. One soft DM surrogate had a total As content of 6,295 mg/kg; toxicity characteristic leaching procedure (TCLP) As of 34.6 mg/L, moisture contents (MCs) between 169 and 200%; and a loss on ignition of 15.4. Two types of SCMs were evaluated. One was a very sandy nonplastic sediment with a total As content of 1,066 mg/kg and TCLP As of 32 mg/L. The other was TCLP As compliant but was more water sensitive, with a total As content of 884 mg/kg and MC of 81%. A treatability study was conducted to determine the S/S treatments, using no more than two reagents simultaneously, that would yield a product meeting all disposal criteria (TCLP As <5 mg/L, pass paint filter test, and maintain a pH between 2 and 12) within 3 days, and be moreover workable. More than 200 mix designs were performed. The conventional approach to immobilizing inorganic arsenic with traditional pozzolans (lime, cement, cement kiln dust, lime kiln dust) led to a doubling of the TCLP As values into the 70 mg/L range. The inclusion of ferric iron was decisive, and combinations of ferric sulfate (wet and dry for As immobilization) with limited quantities of portland cement sufficient to achieve solidification were found to perform the best.

Reactions of iron with calcium carbonate at 6 GPa and 1273–1873 K: implications for carbonate reduction in the deep mantle

Experimental data on Fe-CaCO3 interaction at 6 GPa and 1273–1873 K are presented. The system models the hypothetical redox interaction in subducting slabs at the contact with the reduced mantle and a putative process at the core-mantle boundary. The reaction is accompanied by carbonatite melt formation. It also produces Fe3C and calcium wustite, which form solid or liquid phases depending on experimental conditions. In iron-containing systems at 6 GPa, calcium carbonate melts in the range 1473–1573 K, which is consistent with aragonite disappearance from complex carbonate systems. The composition of calcium carbonate liquid is not influenced by metallic Fe. It corresponds to nearly pure CaCO3. Along the mantle adiabat or at slightly higher temperatures, nearly pure CaCO3 coexists with metallic iron or calcium wustite. This hypothesis explains the coexistence of metallic iron and carbonate inclusions in lithospheric and superdeep diamonds.

Petrology of a nonindigenous microgranitic clast in polymict ureilite EET 87720: Evidence for formation of evolved melt on an unknown parent body

EET 87720 is a polymict ureilite breccia known to contain numerous non-indigenous fragments. We have discovered a microgranitic clast in an interior chip of EET 87720. The clast consists of a granophyre-like intergrowth of a pure SiO2 phase (tridymite) and albite, mantling a zoned oligoclase phenocryst. In the intergrowth, the tridymite occurs as thin elongate vermicular blebs within larger albite crystals. The granophyre-like intergrowth and the oligoclase phenocryst share a common margin, suggesting that the clast was originally part of a larger fragment. An estimate of its bulk composition is equivalent to that of granite (77 wt.% SiO2). Patches of high-Si K-bearing glass occur interstitially within the clast; they have high concentrations of SO3 (11-12 wt.%) and contain Cl (0.6 wt.%), suggesting that the clast formed on a volatile-rich parent body perhaps resembling early Mars. The mean oxygen isotope composition of the feldspar and tridymite in the clast is very different from the oxygen isotope compositions of ureilites, and is similar to those of silicate inclusions in IIE and IVA irons. Thus the clast is not indigenous to the ureilite parent body, but it provides evidence for the formation of evolved melts on an unknown parent body in the early solar system.

Metallurgical Characterization of A Coated Roman Iron Coin By Analytical Investigations

A coated Roman iron coin from Villa Loig in Salzburg, Austria was investigated. The coating is a copper alloy consisting of Cu, Pb, Sn, Zn and negligible amounts of Ag, a variant of gunmetal known as ‘leaded red brass’. The numismatic term for such a coin is subferratus (Latin). From an archaeometallurgical point of view, information about the chemical composition, the microstructure and the manufacturing technique are of interest. To achieve these objectives, different analytical techniques and metallographic examinations were applied. Droplet-shaped iron inclusions were observed in the red brass coating, while at the grain boundaries, inside the iron core, copper and lead were detected (liquid metal embrittlement). The dendritic microstructure of the coating, the spheroidal-shaped iron inclusions in the coating and the liquid metal embrittlement show that the iron coin was plated by immersing it in a molten copper alloy. The iron core is a low-carbon steel with slag stringers, both of which are characteristic of a bloomery iron. Deformation twins (Neumann lines) were observed in the microstructure of the iron core and indicate that the coining was performed after the flan was cooled.

Electrical discharge machining of metal doped Y-TZP/TiC nanocomposites

Electrical discharge machinable dispersion ceramics offer an extraordinary combination of properties such as high hardness, wear resistance, strength and toughness. Furthermore they enable the economic manufacturing of complex shaped parts overcoming the limits these properties imply for their manufacturing by conventional techniques.This study investigates the influence of metallic nanosized inclusions on the ED-machinability and the mechanical properties of zirconia-TiC based ceramics. A 2.6mol% yttria stabilized zirconia with 24vol.% TiC was doped with 2vol.% nanosize inclusions of iron, nickel and cobalt. Samples were hot pressed at 1400°C and 50MPa. Mechanical and electrical properties were measured. Die sink ED-machining was performed and assessed in terms of processing speed and surface quality. Metallic inclusions strongly influenced powder processing and sintering behavior and thus the mechanical properties. Metallic particles reduced the electrical conductivity of the materials and deteriorated ED-machining performance.

Microwave dielectric properties of (Bi1−xFex)NbO4 ceramics prepared by the sol–gel method

(Bi1−xFex)NbO4 (x=0.00, 0.25, 0.50 and 0.75) samples were prepared using the sol–gel method. The fine particles were pressed into cylinders and then treated at temperatures between 350 and 650°C. The structure was studied by X-ray diffraction and the morphology by scanning electron microscopy. The measurements of the complex permittivity were made in a resonant cavity, using the small perturbation method, at frequencies of 2.7 and 5.0GHz. The inclusion of iron allowed a significant decrease in the dielectric losses and more important is to note that it permitted a reduction of the sintering temperature.

Nanocrystals of native iron and titanium in impact glasses of the lunar regolith

The results of examining fragments of impact glasses of the regolith samples from Mare Fecunditatis delivered to the Earth by the Luna 16 Soviet automatic station are presented. Nanosize inclusions of native iron and titanium were found in the samples by means of transmission electron microscopy (TEM). It is shown that these inclusions are constituted of single-crystalline formations. The high-pressure phase of native ω-titanium was discovered naturally for the first time. The data testifying to the high heterogeneity of the glass matrix of regolith grains are presented. Possible mechanisms of the formation of nanocrystals of the treated native phases are discussed.

Efeito do ácido fítico e do ferro inorgânico dietéticos na qualidade da carne suina refrigerada

O estudo foi conduzido com o objetivo de avaliar o efeito da suplementação do ferro inorgânico e do ácido fítico na dieta de suínos em terminação sobre a qualidade da carne após 24 horas e 7 dias de refrigeração. Foram utilizados 40 suínos machos castrados, na fase de terminação, de genética comercial, com 64,34 ± 6,64 kg de peso médio inicial e 108 dias de idade. Os animais foram pesados e alojados individualmente em baias de alvenaria com área de 3 m2 e piso compacto, onde receberam água e ração à vontade durante o período de 30 dias. O delineamento experimental foi em blocos casualizados, em modelo fatorial 2 x 2, sendo os fatores correspondentes às dietas com e sem ferro inorgânico suplementar (FeI) e com dois níveis de ácido fítico (AF) na ração, alto (4,85%) e baixo (2,98%). Ao atingirem 100,76 ± 6,54 kg de peso médio, os animais foram abatidos, sendo coletadas amostras do músculo longissimus dorsi para análise da qualidade da carne. As amostras foram submetidas às avaliações de pH, cor, marmorização, perda de água por pressão, força de cisalhamento, composição de ferro e oxidação lipídica. Os valores das variáveis avaliadas não foram diferentes entre os fatores, excetuando-se a concentração de ferro no músculo, que foi superior para a dieta com a inclusão de ferro inorgânico. A oxidação lipídica não foi influenciada pela presença ou não do AF e FeI. Os resultados demonstraram que dietas com níveis de AF mais elevados, com ou sem a suplementação de FeI, podem ser utilizadas para suínos em fase de terminação sem prejuízos à qualidade da carne durante a fase de refrigeração

Effect of Magnesium on Evolution of Oxide and Sulphide in Liquid Iron at 1873 K

To reveal the effects of magnesium on the evolution of oxide and sulphide inclusions in liquid iron, both thermodynamic calculations and deoxidization experiments were carried out. The samples extracted from the liquid iron were polished and analyzed by optical microscopy and scanning electron microscopy. The results showed that magnesium could modify oxide and sulphide inclusions simultaneously. Spherical MgO and irregular spinel inclusions were observed in the samples. The elongated MnS inclusions were replaced by small MgO • MgS or MgO • MgS • MnS complex inclusions, and the sulphides were distributed dispersively. The evolution mechanisms of inclusions were discussed comprehensively, and a proposed model for the formation of oxysulphide was set up.

Genetic and physiological analysis of tolerance to acute iron toxicity in rice.

BackgroundFe toxicity occurs in lowland rice production due to excess ferrous iron (Fe2+) formation in reduced soils. To contribute to the breeding for tolerance to Fe toxicity in rice, we determined quantitative trait loci (QTL) by screening two different bi-parental mapping populations under iron pulse stresses (1,000 mg L−1 = 17.9 mM Fe2+ for 5 days) in hydroponic solution, followed by experiments with selected lines to determine whether QTLs were associated with iron exclusion (i.e. root based mechanisms), or iron inclusion (i.e. shoot-based mechanisms).ResultsIn an IR29/Pokkali F8 recombinant inbred population, 7 QTLs were detected for leaf bronzing score on chromosome 1, 2, 4, 7 and 12, respectively, individually explaining 9.2-18.7% of the phenotypic variation. Two tolerant recombinant inbred lines carrying putative QTLs were selected for further experiments. Based on Fe uptake into the shoot, the dominant tolerance mechanism of the tolerant line FL510 was determined to be exclusion with its root architecture being conducive to air transport and thus the ability to oxidize Fe2+ in rhizosphere. In line FL483, the iron tolerance was related mainly to shoot-based mechanisms (tolerant inclusion mechanism). In a Nipponbare/Kasalath/Nipponbare backcross inbred population, 3 QTLs were mapped on chromosomes 1, 3 and 8, respectively. These QTLs explained 11.6-18.6% of the total phenotypic variation. The effect of QTLs on chromosome 1 and 3 were confirmed by using chromosome segment substitution lines (SL), carrying Kasalath introgressions in the genetic background on Nipponbare. The Fe uptake in shoots of substitution lines suggests that the effect of the QTL on chromosome 1 was associated with shoot tolerance while the QTL on chromosome 3 was associated with iron exclusion.ConclusionTolerance of certain genotypes were classified into shoot- and root- based mechanisms. Comparing our findings with previously reported QTLs for iron toxicity tolerance, we identified co-localization for some QTLs in both pluse and chronic stresses, especially on chromosome 1.

Modification of Inclusions in Liquid Iron by Mg Treatment

Effect of Mg addition on the compositions of inclusions were studied. The results show that Mg can minimize the inclusions of steel obviously. Under the present condition, Mg deoxidation products of low-S content experimental steel would be changed in the order of Al2O3→MgAl2O4→Mg→Al–O–S→Mg–O–S. Mg deoxidation products of high-S content experimental steel generate Mg–S(–O)+MnS type inclusions, except for usual oxysulfide. And it is consistent with the results of thermodynamics calculation. Mg is preferred to react with oxide, compared with sulfide. The reaction reaches the equilibrium after 1 min or 5 min. It shows that the number and diameter of inclusions in all experimental steel samples are well under control, helping to improve the properties of steel.

Microstructural Features of Bronze-Coated Iron Coins from the Roman Empire

At the late second and early third century coin copies, termed subferrata, were produced in the provinces Noricum and Pannonia of the Roman Empire. Subferrata consist of an iron core, which was plated with a copper alloy. To get information about the manufacturing process and the materials used, coins were cut and investigated after metallographic preparation by light optical microscope (LOM). Scanning electron microscopy (SEM) and energy disperse X-ray analysis (EDX) were used to get information about the local chemical compositions. The general composition was determined by X-ray fluorescence analysis (RFA). The Cu alloy coatings consist of Cu, Pb, Sn, Zn and small amounts of Ag. This alloy is a variant of gunmetal, known as leaded red brass. The coatings show mainly differences in the Pb and Sn content and moreover the intermetallic phase Cu41Sn11was found. Inside the red brass coating droplet-shaped iron inclusions were observed. Near the interface, between coating and iron core, Cu and Pb were detected at the grain boundaries (liquid metal embrittlement). Probably, the iron flan was plated by immersing in a molten copper alloy. In the ferritic-pearlitic iron core, slag inclusions and regions with various carbon contents were observed. Furthermore, deformation twins (Neumann lines) were found in the Fe core ́s microstructure, leading to the suggestion that coining was performed after cooling the flan.

Iron inclusions in plasma cells

Copper deficiency is a rare cause of pancytopenia. We report findings in a 26-year-old female with history of Wilson’s disease diagnosed 13 years previously who was found to be pancytopenic. She was admitted for replacement of a muscle relaxant (baclofen) pump. Full blood examination showed haemoglobin 73 g/L, MCV 90 fl, MCH 26 pg, WCC 1.5 × 109/L, neutrophils 0.7 × 109/L and platelet count 115 × 10 /L. Bone marrow examination revealed a normocellular marrow with dyserythropoeisis, sequential myeloid maturation and increased megakaryocytes. Erythroid and myeloid precursors showed vacuoles in the cytoplasm. There were prominent iron positive inclusions in the plasma cells in the iron stain. The bone marrow findings seen in this patient have been classically described in copper deficiency. One of the treatment modalities in Wilson’s disease is zinc therapy to prevent absorption of copper. The patient was on long term Zinc supplementation (220 mg three times a day). Her serum zinc level was 19.2umol/L, serum copper 0.1 μmol/L and ceruloplasmin 0.02 g/L. While zinc supplementation can be an effective treatment for Wilson’s disease, overtreatment can induce copper deficiency leading to cytopenias with characteristic bone marrow appearance. Recognition is important as copper deficiency can be associated with neurological deterioration due to peripheral neuropathy.

Characterization of Graphite Inclusions in Cast Iron by Cathodoluminescence and X-Ray Microanalysis

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Investigation on the Effect of Sulfur and Titanium on the Microstructure of Lamellar Graphite Iron

The goal of this work was to identify the inclusions in lamellar graphite cast iron in an effort to explain the nucleation of the phases of interest. Four samples of approximately the same carbon equivalent but different levels of sulfur and titanium were studied. The Ti/S ratios were from 0.15 to 29.2 and the Mn/S ratios from 4.2 to 48.3. Light and electron microscopy were used to examine the unetched, color-etched, and deep-etched samples. It was confirmed that in irons with high sulfur content (0.12 wt pct) nucleation of type-A and type-D graphite occurs on Mn sulfides that have a core of complex Al, Ca, Mg oxide. An increased titanium level of 0.35 pct produced superfine interdendritic graphite (~10 μm) at low (0.012 wt pct) as well as at high-S contents. Ti also caused increased segregation in the microstructure of the analyzed irons and larger eutectic grains (cells). TiC did not appear to be a nucleation site for the primary austenite as it was found mostly at the periphery of the secondary arms of the austenite, in the last region to solidify. The effect of titanium in refining the graphite and increasing the austenite fraction can be explained through the widening of the liquidus-eutectic temperature interval (more time for austenite growth) and the decrease in the growth rate of the graphite because of Ti absorption on the graphite. The fact that Ti addition produced larger eutectic cells supports the theory that Ti is not producing finer graphite because of a change in the nucleation potential, but because of lower growth rate of the graphite in between the dendrite arms of a larger fraction of austenite. In the presence of high-Ti and S, (MnTi)S star-like and rib-like inclusions precipitate and act as nuclei for the austenite.

Formation of Alumina Inclusions during Counter Diffusion of Aluminum and Oxygen Dissolved in Molten Iron

The formation of alumina (Al2O3) inclusions was experimentally investigated with the capillary-reservoir method. The inclusions were observed with a SEM (scanning electron microscope). The compositions of iron matrix and inclusion were measured with an EDX (energy dispersive X-ray analysis). The content profile of aluminum was discussed by the counter-diffusion model of aluminum and oxygen with an instantaneous irreversible reaction for alumina formation. The inclusions of spherical and polygonal alumina and spherical hercynite (FeOAl2O3) were observed in the vicinity of the diffusion front of aluminum. The hercynite was detected when the initial oxygen content was 0.075 mass% and higher. When the initial oxygen content was more than 0.045 mass% and higher, dendritic alumina formed at the position that was nearer to the interface than the position of spherical and polygonal inclusions. No inclusion was observed around the interface because of the re-dissolution of the inclusions. The initiating position of the inclusion formation was approximated by the reaction position, Zr, obtained from the model on the assumption that aluminum and oxygen contents at the reaction position were zero. Empirically, 0.9×Zr and 0.17×Zr expressed the initiating positions of formation and re-dissolution of inclusions respectively. The critical supersaturation ratio was estimated to be from 1 to 7.4×105, depending on the initial aluminum and oxygen contents.

Pair breaking caused by magnetic impurities in the high-temperature superconductor Bi2.1Sr1.9Ca(Cu1−xFex)2Oy

Conventional superconductivity is robust against the addition of impurities unless the impurities are magnetic in which case superconductivity is quickly suppressed. Here we present a study of the cuprate superconductor Bi${}_{2}$Sr${}_{2}$Ca${}_{1}$Cu${}_{2}$O${}_{8+\ensuremath{\delta}}$ that is intentionally doped with the magnetic impurity, Fe. Through the use of our tomographic density of states technique, we find that while the superconducting gap magnitude is essentially unaffected by the inclusion of iron, the onset of superconductivity, ${T}_{\mathrm{C}}$, and the pair-breaking rate are strongly dependent and correlated. These findings suggest that, in the cuprates, the pair-breaking rate is critical to the determination of ${T}_{\mathrm{C}}$ and that magnetic impurities do not disrupt the strength of pairing but rather the lifetime of the pairs.