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Showing 1 to 20 of 27 for “"cementite"”.
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ΕΠΙΔΡΑΣΗ ΤΗΣ ΠΑΡΟΥΣΙΑΣ ΤΟΥ ΧΑΛΚΟΥ ΣΤΟΝ ΠΕΡΛΙΤΙΚΟ ΚΑΙ ΜΠΑΙΝΙΤΙΚΟ ΜΕΤΑΣΧΗΜΑΤΙΣΜΟ ΤΩΝ ΧΑΛΥΒΩΝ
… THE PROEUTECTOID PHASES EITHER THE PROEUTECTOID CEMENTITE OR THE PROEUTECTOID FERRITE. WITHING PEARLITESTHE PRESENCE OF SMALL E-CU PRECIPITATES WAS FOUND WITHIN BOTH PEARLITIC FERRITE AND WITHIN PEARLITIC CEMENTITE E-CU PRECIPITATES WITHIN PEARLITIC CEMENTITE ARE OF THE INTERPHASE TYPE AND ARE …
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The first high-strength bainitic steel designed for hydrogen embrittlement resistance
… inconsistent regarding the trapping ability of cementite, with reported trap binding energies ranging from 11 to 66 kJ mol−1. The carbides produced in the alloys were identified as cementite. The cementite fraction was measured to be 0.001 ± 0.0001 for one of the designed alloys, which is the …
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The thermal stability of bulk nanocrystalline steels
… previous work has shown that it decomposes into cementite and ferrite upon heating. This decomposition makes the material weak and brittle. The present work aims to develop new alloys that form nanocrystalline bainite, but which are able to survive heating. Previous work has shown that cementite …
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Effects of vanadium microalloying of 1080 steel on pearlite transformation kinetics and microstructural development
… pearlite ILS and colony size. Grain boundary cementite formation and morphology was evaluated to determine the influence of V in 1080 steel. Vickers microhardness testing was employed to examine the effect of the V addition on hardness. V partitioning/precipitation was analyzed through atom …
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Magnetic Nanoparticles Based on Iron: Synthesis, Characterization, Design, and Application
… thereof: α-iron, iron oxide, and iron carbide or cementite. The synthesis of several core-shell particles including cementite-iron oxide, α-iron-cementite, and α-iron-iron oxide was accomplished through reverse micelle routes and high temperature decomposition of iron pentacarbonyl in various …
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Design and modelling of ultra-high strength steels: nanoprecipitation and plasticity
… The effect of silicon in the epsilon to cementite carbide transition has also been studied. The classical nucleation theory was applied in order to model cementite formation under paraequilibrium conditions, thus incorporating silicon during nucleation. Characterisation using high energy …
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Elevated temperature mechanical properties of line pipe steels
… of transition carbides. Precipitation of cementite, which is associated with low temperature tempering, was theorized to contribute to the relatively high temperature mechanical behavior. Strain assisted bainitic tempering caused a shift in the flow stress maximum to higher temperatures …
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Hydrogen trapping in bearing steels: mechanisms and alloy design
… and heat treatment combining (1) fine cementite providing a strong and ductile microstructure, and (2) nano-sized vanadium carbide precipitates acting as hydrogen traps. A novel technique is proposed to visualise the migration of hydrogen to indentation-induced cracks. The observations …
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Effect of rare earths on the properties of cast iron
… in form in the lower portions of the specimens. Cementite was scattered throughout the matrix of all samples except those. with silicon contents above 2.70 per cent. The metal with didymium additions had the most consistent physical properties, while lanthanum produced the lowest physical …
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Wear Mechanism/microstructure Relationships for Laser Processed Cast Iron (Erosion, Abrasion, Martensite, Transformation)
… sample, the area surrounding interdendritic cementite has a higher density of martensite plates. The frequent intersection of martensite plates induced by deformation in this area causes the initiation of microcracks. Further propagation of these microcracks with continued deformation is …
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Microstructure and mechanical properties of cold drawn steel wires
… spacing, thickness and volume fraction of cementites have all reached the nanometer regime, and the conventional theory is not enough to explain it. Besides, the cementite dissolution is a huge problem to the performance, according to Y.S. Yang and C.G. Park. To address the above issues, a …
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Effect of Microstructure on Mechanical Properties of High Strength Steel Weld Metals
… by large bainitic ferrite grains with cementite precipitates and is believed to form when the bainite and martensite start temperatures are close to each other. Carbon additions were found to promote a more martensitic microstructure throughout the dendrites. Mechanical properties could …
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Effect of Processing Path on Microstructure and Mechanical Properties of a Low Carbon, Low Alloy Advanced High Strength Steel
… a mixture of ferrite, MA microconstituents, and cementite. In water-quenched condition, the microstructure mostly consisted of martensitic lath with a very small fraction of retained austenite and carbides (probably due to auto-tempering). In tempered state, the steel sample comprised of tempered …
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Unidirectional solidification studies of ingot mould cast irons
… liquid iron as well as decomposition of eutectic cementite.
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Effects of copper on wear and rolling-sliding contact fatigue of rail steels
… concentration within the ferrite at the ferrite/cementite interface were observed.
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Direct reduction of iron ore in a rotary kiln
… sponge iron was not in the form of pearlite or cementite. From the microprobe observations it was concluded that the carbon was in the form of soot in the pores of the sponge. A precise study of the progress of reduction from ore to a desirable sponge iron for the different stages of reduction …
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The effect of microstructure on the fracture toughness of a high strength steel
… with the precipitation of lath boundary cementite, Fe3C. Tempering the fine grain material above 400°C eliminated cleavage and brittle intergranular fracture and resulted in a significant increase in toughness. A little brittle intergranular fracture was observed in the coarse grain …
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Failure of Martensitic Sharp Edges: A Micro-Mechanical Exploration for Design Guidelines
… with pearlitic steel showed promising signs of cementite dissolution.
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Understanding toughness and ductility in novel steels with mixed microstructures
… phases are found to be present, namely: cementite and martensite. This is explained as resulting from relatively low alloying additions and chem- ical segregation effects, which are modelled using thermodynamic and kinetic approaches. Chapters 5 and 6 contain a comprehensive study of the …
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