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Grain growth in AZ31 alloy after uniaxial compression

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Transactions of Nonferrous Metals Society of China 2010年第12期20卷 2215-2222页

作者： S.ABdESSAMEUd H.AZZEddINE B.ALILI d.bradai Laboratoire des Matériaux> Faculty of PhysicsUniversity of Sciences and Technology Houari Boumediene(USTHB)BP32El-Alia Bab EzzouarAlgiers 16111Algeria

The grain growth morphology,kinetics and texture change after uniaxial compression at 430 ℃ of an extruded AZ31 alloy were *** samples were loaded following two routes insuring two initial textures of the samples with compression direction parallel and normal to the extrusion *** both initial textures,a stable grain size is attained upon isothermal annealing and the grain growth kinetics can be described by:dn= dRn+kt with an n value of around *** annealing texture with grown grains is a retained hot deformation texture without emerging or strengthening other *** grain growth is not observed for annealing time up to 10 000 h at 450℃.

关键词： AZ31 magnesium alloy uniaxial compression annealing grain growth texture

Unveiling the Residual Stresses,Local Micromechanical Properties and Crystallographic Texture in a Ti-6Al-4V Weld Joint

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 997-1006页

作者： B.Mehdi R.Badji V.Ji B.Alili d.bradai W.Bedjaoui F.deschaux-Beaume F.Brisset Laboratoire de Physique des Matériaux Facul téde PhysiqueUniversitéDes Sciences Et de La Technologie Houari Boumediene16111 AlgerAlgérie Research Center in Industrial Technologies CRTI P.O.Box64CheragaAlgeria ICMMO/SP2M UniversitéParis-Saclay LMGC University of MontpellierCNRSMontpellierFrance

In this work,the micromechanical properties,crystallographic texture,welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4V alloy tungsten inert gas weld *** was found that the welding process affected the Young modulus and microhardness values in bothαandβphases in the different regions of the weld *** highest microhardness and Young modulus values of a phase were recorded in the heat-affected zone,whereas the highest values of these characteristics for theβphase were found in the fusion zone(FZ).The change in the micro mechanical properties was accompanied by a change in the crystallographic texture components of the dominant a phase from(0001)and(11-20)components in the base material to(10-10)and(11-20)components in the *** introduction of tensile testing resulted in a continuous stress relaxation and improved the weld joint performances.

关键词： Ti-6Al-4 V Tungsten inert gas(TIG)weld Residual stress Local mechanical properties Crystallographic texture

Texture evolution in AZ91 alloy after hot rolling and annealing

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Transactions of Nonferrous Metals Society of China 2013年第8期23卷 2215-2221页

作者： B.ALILI H.AZZEddINE K.ABIB d.bradai Faculty of Physics USTHB

A commercial AZ91 magnesium alloy with a random initial texture was subjected to homogenization heat treatment （solution annealing） at 450 ℃. This resulted in the appearance of a weak triple （0001）-（10]-0）-（1120） fibber texture. After hot rolling at 400 ℃, the deformation texture was typically （0001） basal with splitting of the basal poles in the rolling direction. After annealing at 450℃ for 36 h, the annealing texture was the retained deformation texture with more homogeneous distribution of poles around the ideal basal orientation. There was no trace of abnormal grain growth.

关键词： AZ91 alloy texture hot rolling recrystallization

X-ray peak profile analysis of dislocation type,density and crystallite size distribution in cold deformed Pb-Ca-Sn alloys

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Transactions of Nonferrous Metals Society of China 2012年第3期22卷 604-607页

作者： F.ABOUHILOU A.KHEREddINE B.ALILI d.bradai Faculty of Physics University of Sciences and Technology Houari BoumedieneBP 32 El-AliaAlgiersAlgeria

The density,nature of the dislocations and distribution of the domain sizes in cold-deformed Pb-Ca-Sn solid solution were determined by X-ray diffraction profile *** dislocation densities are of the order of 1010 *** strain broadening of diffraction profiles was accounted for by dislocation contrast *** coherent domain size was determined by the recently developed PM2K software *** that the domain size distribution is log-normal,the distribution function（median μ and variance σ） was calculated from the size parameters determined from X-ray diffraction profile analysis.

关键词： Pb-Ca-Sn alloy cold work X-ray diffraction profile analysis(XRdLPA) PM2K software

deformation and recrystallization texture,microstructure and kinetics of Pb-Ca-Sn alloy

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Transactions of Nonferrous Metals Society of China 2011年第8期21卷 1779-1784页

作者： F.ABOUHILOU H.AZZEddINE B.MEHdI B.ALILI d.bradai Laboratoire des Matériaux > Faculty of PhysicsUniversity of Sciences and Technology Houari Boumediene(USTHB) BP32El-Alia Bab Ezzouar16111 AlgiersAlgeria

A Pb-0.08Ca-2Sn alloy was subjected to rolling at room temperature to different final *** treatments at temperature ranging from 80 to 120 °C led to recrystallization of the samples as shown by resistivity and micro-hardness *** deformation texture determined through X-ray diffraction is qualitatively the Brass *** measured Lankford anisotropy parameter R and its evolution are close to the determined one using a self consistent *** R value evolution with angle to rolling direction shows the presence of planar anisotropy and poor *** recrystallization in annealing at 80-120 °C is achieved within time period up to 3×104 *** recrystallization texture is a retained deformation texture with an emerging Cube component.

关键词： Pb-Ca-Sn alloy cold rolling recrystallization texture

dSC analysis of commercial Cu-Cr-Zr alloy processed by equal channel angular pressing

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Transactions of Nonferrous Metals Society of China 2015年第3期25卷 838-843页

作者： K.ABIB F.HAdJ LARBI L.RABAHI B.ALILI d.bradai Faculty of Physics University of Sciences and Technology Houari Boumediene

Samples of a commercial Cu-lCr-0.1Zr(mass fraction,%) alloy were subjected to equal channel angular pressing(ECAP) up to 16 passes at room temperature following route *** scanning calorimetry(dSC) was used to highlight the precipitation sequence and to calculate the stored energy,recrystallization temperature and activation energy after each ECAP *** another hand,electrical properties were correlated with the dislocation *** show that the stored energy increases upon increasing ECAP pass numbers,while the recrystallization temperature decreases significantly.

关键词： equal channel angular pressing(ECAP) Cu-Cr-Zr alloy differential scanning calorimetry(dSC) electrical conductivity stored energy

X-ray diffraction analysis of cold-worked Cu-Ni-Si and Cu-Ni-Si-Cr alloys by Rietveld method

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Transactions of Nonferrous Metals Society of China 2011年第3期21卷 482-487页

作者： A.KHEREddINE F.HAdJ LARBI L.dJEBALA H.AZZEddINE B.ALILI d.bradai Faculté de Physique USTHB BP 32 El-Alia Dar El Beida Alger Algérie

Cold worked and annealed supersaturated Cu-2.65Ni-0.6Si and Cu-2.35Ni-0.6Si-0.6Cr alloys were studied. The microstructural parameters evolution, including crystallite size, root mean square strain and dislocation density was analyzed using Materials Analysis Using diffraction software （MAUd）. The parameters for both alloys have typical values of cold deformed and subsequently annealed copper based alloy. A net change of the crystallite size, root mean square strain and dislocation density values of the alloys aged at 450 °C for 2.5-3 h seems corresponding to the recovery and recrystallization processes. Addition of Cr as quaternary element did not lead to any drastic changes of post deformation or ageing microstructural parameters and hence of recovery-recrystallization kinetics.

关键词： Cu-Ni-Si alloy microstructure XRd line profile analysis Materials Analysis Using diffraction software

do aeolian deposits and sand encroachment intensity shape patterns of vegetation diversity and plant functional traits in desert pavements?

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Journal of Arid Land 2023年第6期15卷 667-694页

作者： M'hammed BOUALLALA Souad NEFFAR Lyès bradai Haroun CHENCHOUNI Laboratory of Saharan Natural Resources Faculty of Sciences and TechnologyUniversity of Ahmed DraiaAdrar 01000Algeria department of Nature and Life Sciences Faculty of Exact Sciences and Nature and Life SciencesUniversity of TebessaTebessa 12002Algeria Laboratory Water and Environment University of TebessaTebessa 12002Algeria Laboratory of Saharan Bioresources Preservation and Valorization Faculty of Nature and Life SciencesUniversity of Kasdi MerbahOuargla 30000Algeria department of Forest Management Higher National School of ForestsKhenchela 40000Algeria Laboratory of Natural Resources and Management of Sensitive Environments University of Oum-El-BouaghiOum-El-Bouaghi 04000Algeria

The effects of sand encroachment on composition,diversity,and functional patterns of vegetation in drylands are rarely studied,and yet addressing these aspects is important to deepen our understanding of the biodiversity *** study aimed to investigate the effect of sand encroachment on plant functional biodiversity of desert pavements(gravel deserts)in the Sahara desert of *** were sampled and analyzed in three desert pavements with different levels of sand encroachment(LSE)and quantity of aeolian deposits(low,LLSE;medium,MLSE;and high,HLSE).Within the sample-plot area(100 m^(2)),density of every plant species was identified and total vegetation cover was *** taxonomic and functional diversity were analyzed and compared between *** showed that 19 plant species in desert pavements were classified into 18 genera and 13 *** and Poaceae were the most important *** species Anabasis articulata(Forssk)*** LLSE desert pavements with 11 species,whereas Thymelaea microphylla Coss.&durieu ex *** Calobota saharae(C&d)Boatwr.&van Wyk were dominant species of desert pavements with MLSE(14 species)and HLSE(10 species),*** highest values of species richness and biodiversity were recorded in desert pavements with MLSE,while low values of these ecological parameters were obtained in desert pavements with *** pavements with LLSE were characterized with the highest values of species *** communities were dominated by chamaephytes,anemochorous,arido-active,and competitive stress-tolerant *** increase in LSE along the gradient from LLSE to HLSE induced significant changes in plant community variables including decreases in plant density,plant rarity,lifeform composition,morphological type,and aridity *** pavements with HLSE favor the degradation of vegetation and trigger biodiversity erosion.

关键词： desert pavements hot and arid rangeland plant diversity land degradation sand encroachment plant functional trait Sahara desert

Microstructural and textural investigation of an Mg-dy alloy after hot plane strain compression

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Journal of Magnesium and Alloys 2020年第4期8卷 1198-1207页

作者： Fairouze Guerza-Soualah Hiba Azzeddine Thierry Baudin Anne-Laure Helbert Frangois Brisset djamel bradai Laboratory of Materials Physics Faculty of PhysicsUniversity of Sciences and Technology-Houari Boumediene(U.S.T.H.B.)P.O.Box 32El-AliaBab-EzzouarDZ-16111AlgiersAlgeria Faculty of Technology University of Mohamed BoudiafM'Sila 28000Algeria CNRS Institut de Chimie Moleculaire et des Materiaux d'OrsayUniversite Paris-Saclay91405 OrsayFrance

The microstructure and texture development in a Mg-0.41dy(wt%)alloy after plane strain compression(PSC)at 300℃under a strain rate of 10^(-2)and 10^(-4)s^(-1),up a final true strain of—1.2 were investigated using electron backscatter diffraction(EBSd)and X-ray *** high strain rate of 10^(-2)s^(-1),the microstructure exhibited massive twins mainly{101^(-)2}extension,{1011}contraction and{101^(-)3}-{101^(-)2}double twin due to the random texture of the as-cast ***,at a low strain rate of 10^(-4)s^(-1),the microstructure was characterized by dynamic recrystallization at the{101^(-)2}extension,(101^(-)1)contraction twins and grain *** dynamic recrystallization(TdRX),rotational dynamic recrystallization(RdRX)and discontinuous dynamic recrystallization(ddRX)were the main mechanisms responsible for the formation of recrystallized *** texture was characterized by the formation of three fibers:basal,//Cd and//Cd where Cd is the compression ***,the texture was less sensitive to the deformation conditions since the recrystallized grains showed the same orientation than *** changes of the mechanical properties of the alloy were ascribed to the resulting microstructure due to the twinning and dynamic recrystallization.

关键词： dynamic recrystallization PSC Mg-dy alloy Texture Twinning.