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Deformation texture prediction: from the Taylor model to the advanced Lamel model

The cold rolling texture of low and extra low carbon steels is primarily made up of a nearly perfect normal direction (ND) fibre and of two other components, centred at 001 and 112 , which...

Cold rolling and annealing textures in low carbon and extra low carbon steels

During the controlled rolling of steel, the parent γ phase develops a crystallographic texture which is later acquired by the material after transformation. The major components of the deformation ...

Transformation textures in steels

The mechanical behavior of the commercial aluminum alloy AA5182-O is investigated at temperatures ranging from −120 to 150 ◦ C and strain rates from 10 −6 to 10 −1 s −1 . The strain rate sensitivity parameter is determined as a function of temperature and plastic strain, and the strain rate and temperature range in which dynamic strain aging leads to negative strain rate sensitivity is mapped. The effect of dynamic strain aging on ductility and strain hardening is investigated. The sensitivity of the measured quantities to the experimental method employed and their dependence on grain shape are discussed. The experimental data are compared with the predictions of a model constructed based on a recently proposed mechanism for dynamic strain ageing. The mechanism is based on the effect solute clustering at forest dislocations has on the strength of dislocation junctions. The model is shown to reproduce qualitatively the experimental trends. © 2004 Elsevier B.V. All rights reserved.

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Strain rate sensitivity of the commercial aluminum alloy AA5182-O

The mechanism of the texture formation in low carbon steels is not fully understood as yed. To clarify this, a series of systematic investigations has been made. Summarizing these results and comparing these with those of other investigations, possible mechanisms of texture formation are discussed. In polycrystalline iron, deformation and recrystallization in grain boundary regions play the most important role in the texture formation. In this respect, results obtained on single and bi-crystals do not provide much informations. In polycrystals, crystal rotation occurs during rolling along different paths from that observed in single crystals, affected by grain boundary constraints significantly. Approaches to the stable end orientation seems to be closely related with the development of the stable dislocation substructures. The development of the rolling texture is therefore strongly affected by the metallurgical factors that influence the evolution of the dislocation substructures. {111} recrystallized grains seem to be formed from the grain boundary regions of the same orientation through the subgrain growth mechanism.

Fundamental Aspect of Texture Formation in Low Carbon Steel.

The effect of crystallographic texture on the anisotropies of strength and toughness of the controlrolled high tensile steels was quantitatively investigated . The effect of the textures on the anisotro.bies of yield and tensile strees could be accurately evaluated with Hosford and B ackofen's method, if fine de tails of textures were properly taken in to account. The anisotropies of toughness were found to be qualitatively related with the dis tribution of { 100} cleavage plane. 1 t was f urther found that among the main components of the textures of tlzese steels, {3 1J }<01J> orientations not only enhanced the difference in stmlgth between L (OO) and C(900) directions, but also reduced the toughness at 45° direction, whereas {332}< 113> orientations gave rise to a weak anisotropy and better average strength and toughness . T hus, f urther im/Jrovemen t in strength and toughness might be eX/Jected,ij /Jreferential development of {332}< 113> orientations was to be achieved .

https://www.jstage.jst.go.jp/article/tetsutohagane1955/61/7/61_7_991/_pdf

Influence of Crystallographic Texture on the Strength and Toughness of the Controlled Rolled High Tensile Strength Steel

Influence of Crystallographic Texture on the Strength and Toughness of Control-rolled High Tensile Strength Steel

Development of sharp {111} recrystallization texture in polycrystalline iron can not be explained by simply synthesizing the results obtained so far on single crystals Since this strongly suggests that this phenomenon is related with the presence of grain boundaries, it was tried to clarify the origin of this texture component by studying the rolling and recrystallization textures of polycrystalline specimens having sharp initial texturesIt was found that the interaction between differently oriented neighbouring grains during rolling was quite aniotropic This suggested that orientations of recrystallized grains nucleated near grain boundary should not be random It was further suggested that, if the stable end orientations of two neighboring grains were the same, their boundary regions were forced during rolling to rotate into these common end orientations, so that stress and strain compatibilities could be satisfied concurrently Since these regions are highly strained, they could provide recrystallization nuclei Such interactions among the members of fiber texture having axes parallel to the normal direction would produce highly strained regions having {111} common end orientations Among them, the interaction between {111} and {111} initial orientations provided the most potential nuclei of {111} recrystallization texture which is typically found in the commercial Al-killed steel

Formation of {111} Recrystallization Texture in Polycrystalline Iron

A 0.1%C-1.35%Mn-0.03%Nb steel was hot rolled in a single pass up to 83% reduction in thickness at a temperature between 790°C and 1 050°C and the deformation state of austenite was examined metallographically in detail. It was found that annealing twins were formed abundantly in the austenite during heating before rolling, or during recrystallization in a high temperature. Rolling at a temperature below the recrystallization temperature of austenite resulted in a severe deformation of these annealing twins. At the same time, a heavy local deformation was introduced into the regions near boundaries of these annealing twins, and also near austenite grain boundaries. Such a local concentration of deformation was found to enhance the formation of ferrite nuclei in these regions during the subsequent ferrite-pearlite transformation. It was suggested that this effect was most essential in the grain refinement of control-rolled steel.

Hirosuke Inagaki

Papers

Fundamental Aspect of Texture Formation in Low Carbon Steel.

Influence of Crystallographic Texture on the Strength and Toughness of the Controlled Rolled High Tensile Strength Steel

Influence of Crystallographic Texture on the Strength and Toughness of Control-rolled High Tensile Strength Steel

Formation of {111} Recrystallization Texture in Polycrystalline Iron

Role of Annealing Twins for Grain Refinement in Controlled Rolling of Low Carbon Microalloyed Steel