8509

7890

كارشناسي ارشد

شناسايي و انتخاب مواد

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد

1392

يازده،82ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

محمود مرآتيان، غلامرضا آريانپور

مسعود پنجه پور

15/11/92

احمد رضائيان، ابوذر طاهرزاده

مهندسي مواد

ID7890

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

91 Characterization of Ultrafine Grained 5086 Al Mg Alloy Synthesised by ECAP Process Mohammad Hossein Khaleghifar mh khaleghifar@ma iut ac ir Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisors M Meratian meratian@cc iut ac ir G R Aryanpour aryanmat@cc iut ac ir Advisor M Panjehpour panjepour@cc iut ac ir Abstract Aluminum and its alloys are the most consumable non ferrous metals The 5086aluminum alloy enjoys a vast variety of properties including low price high strength toweight ratio high fatigue strength excellent corrosion resistance against salt water goodductility and good weldability while non heat treatable The severe plastic deformation SPD processes are basically applied for the large strain to solid bulk materials withoutsignificant changes in specimen s overall dimensions Among different SPD techniques Equal Channel Angular Pressing has attracted most attentions because of manufacturingcommercial capability and industrial facilities In this research ECAP process up to 10passes was carried out on a rolled 5086 Al Mg alloy with different routes of A and Bc inthe ECAP die with 120o at 150 oC Tensile and hardness tests were performed Inorder to clarify the failure mode fracture surfaces of tensile test were observed byScanning Electron Microscopy SEM Moreover X ray diffraction XRD system wasutilized to investigate the texture variations using for calculating the texture parameters andcomparing the X ray diffraction patterns of samples The microstructures were evaluatedwith SEM equipped by EBSD system The results showed that the hardness was increasedsignificantly in initial passes Also with increasing the number of passes increasing rate ofhardness decreased The same trend was observed in tensile strengths It was observed thatat first stages of ECAP process Sample s Elongations strongly decreased from 34 7 to 22 4percent and in next passes the rate was decreased Fractographic observations showed thatthe number of dimples were increased with increasing the number of passes Texture studyof samples showed that 220 planes were as predominant texture by ECAP process It wasbelieved that according to the results the ECAPed samples for 4 passes with route Bc hardness of 111 HV 337 MPa tensile strength and elongation of 21 had the mostfavorable mechanical properties and microstructures Keywords 5086 Al Mg Sever Plastic Deformation ECAP Hardness Tensile Strength Fractography Texture Microstructure

محمود مرآتيان، غلامرضا آريانپور

مسعود پنجه پور

احمد رضائيان، ابوذر طاهرزاده