scholarly journals The Microstructure and Deformation Behavior of Al-Fe-Mn Alloys with Different Fe Contents during Cold Rolling

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 753 ◽  
Author(s):  
Yanfeng Pan ◽  
Yifu Shen ◽  
Pizhi Zhao

The microstructure transformations and deformation behavior of Al-Fe-Mn alloys with different Fe contents during their cold rolling process were investigated by means of hardness testing, conductivity testing, and transmission electron microscopy. It was observed that the hardness of the two alloys increased initially along with the levels of cold rolling reduction, then reduced when levels of cold rolling reduction increased further. Two kinds of deformation behaviors, work hardening and work softening, were observed during cold rolling for both Al-Fe-Mn alloys with different Fe contents. The critical level of cold rolling reduction that led to the change from work hardening to work softening was different in both alloys and the critical level of cold rolling reduction of the alloy with high Fe content was significantly lower than that of the alloy with low Fe content. During the work hardening process, the number of dislocations in the alloys increased continuously as the level of cold rolling reduction increased and they were accompanied by the formation of substructures. After the occurrence of work softening, the dislocation density in the alloys was significantly reduced. The sub-grain structures polygonized and ultimately transformed into equiaxed sub-grains.

2016 ◽  
Vol 877 ◽  
pp. 380-386 ◽  
Author(s):  
Yan Feng Pan ◽  
Pi Zhi Zhao ◽  
Yi Fu Shen ◽  
Xiang Jun Shi ◽  
Tao Jiang

The deformation behaviours and microstructure transformations during the cold rolling process of Al-1.4Fe-0.2Mn alloy sheets prepared from 99.7% pure aluminium were investigated by means of hardness-testing, transmission electron microscopy (TEM) and energy dispersive spectrometer (EDS). The phenomena of work hardening and work softening were observed. The hardness of Al-1.4Fe-0.2Mn alloy sheets increased with the increasing of cold rolling reduction firstly, and reached to a peak at 80% cold rolling reduction, meaning work hardening. However, with further increasing of cold rolling reduction, the hardness decreased, which indicates work softening. During the initial deformation stage, the dislocation density and the number of sub-grain structures increased gradually, and many dislocations formed tangles, resulting in work hardening. When the cold rolling reduction exceeded 80%, the dislocation density decreased and sub-grain structures polygonized, leading to work softening. The forming of Mn, Fe and Si bearing compounds is an important reason for the work softening due to lowering solid solution content.


Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 187
Author(s):  
Bo Zhang ◽  
Li Meng ◽  
Guang Ma ◽  
Ning Zhang ◽  
Guobao Li ◽  
...  

Twinning behaviors in grains during cold rolling have been systematically studied in preparing ultra-thin grain-oriented silicon steel (UTGO) using a commercial glassless grain-oriented silicon steel as raw material. It is found that the twinning system with the maximum Schmid factor and shear mechanical work would be activated. The area fraction of twins increased with the cold rolling reduction. The orientations of twins mainly appeared to be α-fiber (<110>//RD), most of which were {001}<110> orientation. Analysis via combining deformation orientation simulation and twinning orientation calculation suggested that {001}<110> oriented twinning occurred at 40–50% rolling reduction. The simulation also confirmed more {100} <011> oriented twins would be produced in the cold rolling process and their orientation also showed less deviation from ideal {001}<110> orientation when a raw material with a higher content of exact Goss oriented grains was used.


2006 ◽  
Vol 524-525 ◽  
pp. 821-826 ◽  
Author(s):  
Peter Hedström ◽  
Jonathan Almer ◽  
Ulrich Lienert ◽  
Magnus Odén

The deformation behavior of metastable austenitic stainless steel AISI 301, suffering different initial cold rolling reduction, has been investigated during uniaxial tensile loading. In situ highenergy x-ray diffraction was employed to characterize the residual strain evolution and the strain induced martensitic transformation. Moreover, the 3DXRD technique was employed to characterize the deformation behavior of individual austenite grains during elastic and early plastic deformation. The cold rolling reduction was found to induce compressive residual strains in the austenite along rolling direction and balancing tensile residual strains in the ά-martensite. The opposite residual strain state was found in the transverse direction. The residual strain states of five individual austenite grains in the bulk of a sample suffering 2% cold rolling reduction was found to be divergent. The difference among the grains, considering both the residual strains and the evolution of these, could not be solely explained by elastic and plastic anisotropy. The strain states of the five austenite grains are also a consequence of the local neighborhood.


2005 ◽  
Vol 495-497 ◽  
pp. 603-608 ◽  
Author(s):  
Atsushi Todayama ◽  
Hirosuke Inagaki

On the basis of Taylor-Bishop-Hill’s theory, many previous theoretical investigations have predicted that, at high rolling reductions, most of orientations should rotate along theβfiber from {110}<112> to {123}<634> and finally into the {112}<111> stable end orientations. Although some exceptions exist, experimental observations have shown, on the other hand, that the maximum on the β fiber is located still at about {123}<634> even after 97 % cold rolling. In the present paper, high purity Al containing 50 ppm Cu was cold rolled up to 99.4 % reduction in thickness and examined whether {112}<111> stable end orientation could be achieved experimentally. It was found that, with increasing rolling reduction above 98 %, {110}<112> decreased, while orientations in the range between {123}<634> and {112}<111> increased, suggesting that crystal rotation along the βfiber from {110}<112> toward {123}<634> and {112}<111> in fact took place. At higher rolling reductions, however, further rotation of this peak toward {112}<111> was extremely sluggish, and even at the highest rolling reduction, it could not arrive at {112}<111>. Such discrepancies between theoretical predictions and experimental observations should be ascribed to the development of dislocation substructures, which were formed by concurrent work hardening and dynamic recovery. Since such development of dislocation substructures are not taken into account in Taylor-Bishop-Hill’s theory, it seems that they can not correctly predict the development of rolling textures at very high rolling reductions, i. e. stable end orientations. On annealing specimens rolled above 98 % reduction in thickness, cube textures were very weak, suggesting that cube bands were almost completely rotated into other orientations during cold rolling. {325}<496>, which lay at an intermediate position between {123}<634> and {112}<111> along theβfiber, developed strongly in the recrystallization textures.


Sign in / Sign up

Export Citation Format

Share Document