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Showing 1 to 18 of 18 for “"austenite grain size"”.
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Austenite grain-size control at elevated temperature in microalloyed carburizing steels
Includes bibliographical references (pages 194-208).
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Investigating the Effect of Austenite Grain Size and Grain Boundary Character on Deformation Twinning Behavior in A High-Manganese TWIP Steel: A TEM In-Situ Deformation Study
… and generally appears in most ultrafine-grained metals. The ultrafine-grained (UFG) high manganese austenitic twinning-induced plasticity (TWIP) steels have been found to overcome the strength-ductility trade-off but their underlying mechanism of discontinuous yielding behavior has not …
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The influence of rough rolling conditions on austenite evolution in peritectic microalloyed plate steels
… stages of hot rolling where pancaking of the austenite is desired for strength and toughness. During roughing, full recrystallization is desired for a uniform, through-thickness austenite microstructure. In this work the influence of the strain sequence during roughing on the evolution of …
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The effect of non-metallic particles on as-cast austenitic structure of low carbon steel
… particles and cooling rate on the as-cast austenite grain size of peritectic plain-carbon steel has been examined. Remelting tests followed by continuous cooling and helium quenching were performed on a Gleeble 1500 Thermo mechanical Simulator. Two low alloy types of steel were used; both …
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Microstructure of Flash processed Steel Characterized by Electron Backscatter Diffraction
… steel sheet or strip to a temperature in the austenite range and quenching; the entire thermal cycle takes place within 15 seconds. The resulting microstructure is fine and difficult to resolve using standard metallographic techniques. In this investigation, electron backscatter diffraction …
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Development of third generation advanced high strength steels
… of either bainite, acicular ferrite, and austenite or martensite and austenite were investigated as third generation advanced high strength steels targeted for automotive applications. Large additions of manganese (>13 wt%) and carbon (</p> <p>Duplex steels with different volume fractions …
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Fatigue in low pressure carbonitrided steels
… four alloys. The profiles for hardness, retained austenite, residual stress, carbon and nitrogen were comparable for all the alloys. However, the fatigue performance of each alloy was different. The highest endurance limit was attained by 20MnCr5+B, followed by 20MnCr5, SAE 8620+Nb, and SAE 8620. …
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Modelo Termo-mecânico-metalúrgico de chapa de aço naval DH36 soldada com MAG/John
… of the microstructures considering the prior austenite grain size, through a method proposed from welding CCT diagrams. In the mechanical model, the constitutive equations were modified, using the finite element program subroutines to introduce the increments of the deformations due to the …
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Mathematical modelling of the onset of transformation from austenite to pearlite under non-continuous cooling conditions
… rule in relation to the incubation of the austenite decomposition. An "ideal" isothermal transformation curve for 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 …
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Modelling of Simultaneous Transformations in Steels
… developed by solid-state transformation from austenite. The major transformation 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 …
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Effect of microalloying on pearlite transformation of high carbon wire steels
… trends in hardness and microstructural feature sizes observed in continuous cooling tests persist through industrial hot rolling simulations. An industrially hot rolled 1080 wire rod with vanadium additions and three laboratory-prepared alloys were studied. The base alloy, denoted the V steel, …
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Einfluss der Prozesskette auf die Feinkornbeständigkeit von mikrolegierten Einsatzstählen
… temperature, the appearance of prohibited coarse austenite grains has to be avoided. However the former austenite grain size is an attribute of the overall process chain from steel melting to case hardening. In this work, the influence of the manufacturing process on grain size stability of case …
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Effect of equalisation time and temperatures on microstructures of simulated directly and conventionally charged V - microalloyed steels
… not have a sufficient ability to prevent the austenite grains from growing during the equalisation. Because of the slow precipitation, AIN only precipitates at the longest equalisation time and is the main compound which has an obvious pinning effect on the austenite grain growth in …
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The Effect of Niobium in the Heat-affected Zone of Microalloyed Steel
The controlled, _ne-grained microstructure of thermomechanically processed Nb microalloyed linepipe steels is destroyed in the vicinity of welds used in fabricating pipelines. There are conflicting views on the influence of niobium in the `heat-affected zone', particularly in the region closest to …
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Transformation and precipitation in vanadium treated steels
… in relation to the solubility of VC and VN in austenite, the grain coarsening characteristics of austenite, the tempering of martensite and other structures, the transformation during continuous cooling, the effect of vanadium addition and increasing nitrogen content on the thermo-mechanical …
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Multiphase particle-size-grouping model of precipitation and its application to thermal processing of microalloyed steel
… for example, precipitates may lead to beneficial grain refinement or detrimental transverse surface cracks. A comprehensive set of models has been developed to determine precipitate formation during metal processing. They include an equilibrium precipitation model and kinetic models for …
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Modelling of Microstructure Development in Silicon-containing Bainitic Free-machining Steels
… conditions. A model for estimating retained austenite size distribution in the carbide-free bainitic microstructure has been developed. Manganese sulphide particles are used in the free-machining steel to break chips during machining; its effect on the prior austenite grain size has been …
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Understanding the Stability of Retained Austenite in High-Carbon Steels: Modelling and Alloy Design
In high-carbon steels, the austenite-to-martensite transformation under applied stress initiates at a critical value, contrary to low-carbon steels where the transformation occurs at the early stages of deformation. There are few models that account for the delayed transformation, because previous …