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Showing 1 to 20 of 28 for “"Pearlite"”.
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Wear of fine pearlite, nanostructured bainite and martensite
… achieved by changing the structure from pearlite, nanostructured bainite to martensite by heat treatment, do not lead to significant differences in the wear rate. This is because the wear mechanisms change, for example from severe sub-surface deformation leading to sticking in the case of …
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The effect of interrupted quenching on the pearlite transformation.
Massachusetts Institute of Technology. Dept. of Metallurgy and Materials Science. Thesis. 1973. Ph.D.
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Effect of microalloying on pearlite transformation of high carbon wire steels
… eutectoid steels showed delayed pearlite transformation with additions of niobium and accelerated pearlite transformation with additional nitrogen. This study investigates the origin of the CCT shifts with microalloying additions and whether trends in hardness and microstructural …
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Effects of vanadium microalloying of 1080 steel on pearlite transformation kinetics and microstructural development
The effects of V alloying on the pearlite transformation kinetics and microstructure in 1080 steel were evaluated. Two industrial wire rod steels, 1080 and 1080V with a 0.035 wt pct V addition, were isothermally heat treated using dilatometry to assess pearlite transformation rates. A detailed …
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Mathematical modelling of the onset of transformation from austenite to pearlite under non-continuous cooling conditions
… the start of transformation from austenite to pearlite has been developed based on the assumption of the consumed fractional incubation time being additive. The curve is characteristic of the chemistry and the austenite grain size of the steel. A mathematical relationship between the …
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Microstructure -Level Machining Modeling of Ferrous Alloys
… of ductile iron and two of its constituents: pearlite and ferrite. Orthogonal cutting experiments and simulations were conducted of the three materials. The measured chip morphology and machining forces were compared with the model predictions, and a good correlation between them was found. In …
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Modeling the microstructure development in gray iron castings
… and white iron, graphite morphology, percent pearlite, percent ferrite and pearlite spacing. The predicted microstructure can then he used to determine the strength and fatigue properties using published correlations. This model will provide a powerful tool in optimizing casting and design …
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Investigation of microstructural evolution by real-time SEM of high-temperature specimens.
… the number of nuclei initiating the austenite-to-pearlite transformation is small by comparison to the number of austenite grains present and that the austenite-to-pearlite transformation front sweeps from grain to grain with relative ease.
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Some aspects of crack initiation in mild steel subjected to fatigue stressing in a corrosive environment
… Preferential attack also occurs at the ferrite - pearlite interfaces, at slip band - matrix interfaces, and at grain boundaries. All these modes of attack can lead to crack nucleation. It has also been found that non-metallic inclusions can act as sites for hydrogen blisters; this may assist the …
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On the Modeling and Analysis of Machining Performance in Microendmilling
… 5 microns were used to machine slots in ferrite, pearlite and two ductile iron materials at feedrates ranging from 0.25 to 3.0 microns/flute. A surface generation model to predict the surface roughness for the slot floor centerline is then developed based on the minimum chip thickness concept. Two …
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The strengthening and "softening" of low-carbon structural steels by silicon
… were used to characterize the ferrite-pearlite structures, decarburized layers, random interlamellar spacings in the pearlite constituent, slip line, twin and dislocation structures. The precipitates observed were studied qualitatively with the transmission electron microscope, and …
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The Effect of Milling Time on the Structure and the Properties of Mechanically Alloyed High Carbon Iron-Carbon Alloys
… from powders milled for 0.5h. The amount of the pearlite decreased with milling time, contrary to what was found in the literature. The decrease in pearlite occurred at the same time as an increase in graphite-rich areas. With milling, carbon tended to form graphite instead of Fe_3 C. Longer …
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ΕΠΙΔΡΑΣΗ ΤΗΣ ΠΑΡΟΥΣΙΑΣ ΤΟΥ ΧΑΛΚΟΥ ΣΤΟΝ ΠΕΡΛΙΤΙΚΟ ΚΑΙ ΜΠΑΙΝΙΤΙΚΟ ΜΕΤΑΣΧΗΜΑΤΙΣΜΟ ΤΩΝ ΧΑΛΥΒΩΝ
… COPPER ON THE ISOTHERMALLY PRODUCED BAINITE OR PEARLITE WAS INVESTIGATED, IN COPPER BEARING STEELS, TO GAIN A BETTER UNDERSTANDING OF ROW COMMONSUBSTITUTIONAL SOLUTES INFLUENCE PEARLITIC TRANSFORMATION IT WAS FOUND THAT PRECIPITATES BELONGING TO THE PHASE E-CU EXISTED WITHIN THE PROEUTECTOID …
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Bauschinger effect in Nb and V microalloyed line pipe steels
… composition of structural steels with a ferrite-pearlite microstructure has been developing towards decreasing carbon content, to increase weldability, with increased microalloying element content, to provide grain refinement, solid solution and precipitation strengthening. During the UOE forming …
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Modelling of Microstructure Development in Silicon-containing Bainitic Free-machining Steels
… allotriomorphic ferrite, idiomorphic ferrite, pearlite, Widmanstatten ferrite, bainite and martensite. The effect of recalescence has been included to give a better estimation of the cooling curve under natural cooling conditions. A model for estimating retained austenite size distribution in …
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The effect of copper on the eutectoid transformation in ductile iron
… of copper during solidification is key to the pearlite promoting effect of copper and is related to the decrease in the driving force for the diffusion of carbon through the ferrite shell.
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Modelling of Simultaneous Transformations in Steels
… products are allotriomorphic ferrite, pearlite, Widmanstatten ferrite, bainite and martensite, differentiated by morphological features, and their nucleation and growth mechanisms. A steel often consists of several phases as a result of dynamic evolution during continuous cooling. The …
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Experiments augmented computational analysis of structural materials: A focus on metallic and biological systems
… the structure-property relationships and design pearlite lamellae for optimized mechanical performance. Furthermore, the study extends to bio-inspired materials, investigating Nacre like structures for topology optimization aimed at enhancing mechanical properties and wave filtering capabilities. …
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Creep crack initiation and growth in 2.25% chromium - 1% molybdenum alloy steel
… > mixed ferrite / bainite > mixed ferrite / pearlite.</p> <p>A correlation between the carbide type, distribution and shape and the creep deformation and crack initiation process has been discussed and the implications of this to remanent life assessment suggested. Evolution of …
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Elevated temperature mechanical properties of line pipe steels
… evaluated. The four materials include a ferrite-pearlite line pipe steel with a yield strength specification of 359 MPa (52 ksi) and three 485 MPa (70 ksi) yield strength acicular ferrite line pipe steels. Deformation behavior, ductility, strength, strain hardening rate, strain rate sensitivity, …
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