10460

9655

كارشناسي ارشد

جوشكاري

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مهندسي مواد

1394

چهارده، 102ص.: مصور، جدول، نمودار

مرتضي شمعانيان، حميدرضا سليمي جزي

1394/07/04

حسين ادريس، صالح اكبرزاده

1396/10/04

كتابنامه

مواد

مهندسي مواد

ID9655

به فارسي و انگليسي

Microstructure modification of Al2024 and fabrication of surface compositesof Al2024 SiC and Al2024 SiC MoS2 via friction stir processing and investigation of its microstructure and tribological behavior Seyed Mohammad Mirhoseini M mirhoseini@ma iut ac ir August 17 2015 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisors Dr M Shamanian Prof e mail shamanian@cc iut ac irDr H Salimi Associate Prof e mail hrjazi@cc iut ac irAbstractIn the present study friction stir processing was used to modify 2024 Aluminium alloymicrostructure and fabricate Al SiC surface composites and Al SiC MoS2 hybridcomposite surface For this purpose tool traverse speed of 20 mm min and tool rotationalspeeds of 1000 1250 1600 and 2000 rpm with 3 tool tilt angle were applied In modifiedaluminium samples via FSP substantial reduction of grain size from 50 m to 4 m in thestir zone were observed In addition erosion evaluation indicated the improvement oftribology properties in friction stir processed samples although precipitates coarsening solutioning caused hardness decrease of stir zone Tribology properties were morepronounced in lower tool rotational speeds which can be due to grain size reductionleading to higher hardness and slight coarsening and solutioning of precipitates The effectof the direction of tool rotation changes on the distribution of reinforcement particles ineach pass was evaluated It was found that the direction of tool rotation change can resultin more uniform distribution of reinforcement particles in each pass Therefore all theexperiments were carried out in 4 passes with a change in the direction of tool rotation perpass The highest tool rotational speed of 2000 rpm led to the greatest erosion properties insingle component and hybrid composites Lower hardness of these samples can be relatedto more coarsening and solutioning of precipitates due to high too rotational speed However improved erosion properties is attributed to more uniform distributed and finerparticles In similar tool rotational speed despite higher hardness of single componentcomposites with respect to hybrid composites they demonstrated better tribologycharacteristics than Al SiC surface composites owing to the presence of MoS 2reinforcement particles ductile and lamellar structure and acting as a solid lubricant andformation of a stable complex mechanical layer on the surface of hybrid composites Theinvestigation on erosive particles revealed that the dominant erosion mechanism in themodified and composites samples are adhesive and abrasive erosion of different severity respectively Key words Friction stir processing Tribological behavior Hybrid composite Mechanically mixed layer

مرتضي شمعانيان، حميدرضا سليمي جزي

حسين ادريس، صالح اكبرزاده