9837

9074

كارشناسي ارشد

شناسايي و انتخاب مواد

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد

1393

سيزده، 66ص.: مصور، نمودار

ص.ع. به فارسي و انگليسي

محمدرضا طرقي نژاد

94/2/1

حسين ادريس، احمدرضاييان

1396/09/26

كتابنامه

مواد

مهندسي مواد

ID9074

67AbstractIn this study the effects of strain routes in Accumulative Roll Bonding ARB on themechanical properties and microstructure of sheet aluminum samples were examined Theroutes were considered as direct rolling route A and cross roll accumulative roll bondingby the rotation angle of 90 degrees in one direction continuously route BC 90 routeBA and 180 route c This study used commercial pure aluminum sheets with thethickness of 1 mm and the dimensions of 5 15 cm for direct rolling in 180 degrees and10 10 cm for the rotation of 90 degrees Studies addressing the mechanical propertiesthrough hardness machine and tensile route test have shown that due to the increase indislocation density and finer grains the hardness and tensile strength were increased by thenumber of cycles in the processes However the growing increase of hardness and strengthin the rolling route by the rotation angle of 180 degrees was considered as the maximumvalue due to anisotropy and higher dislocation density On the other hand the minimumvalue was found to be in the direction of 90 due to the Baushinger effect anisotropyand dislocation density Hardness after 8 cycles compared to the annealed sample inroutes A C BC and BA was found to be 2 60 2 63 2 56 and 2 51 times respectively Byapplying the first cycle processes yield and tensile strength were increased intensively butthe rate of increase in strength was decreased in the subsequent cycles Also the strength after 8 cycles compared to the annealed sample in routes A C BC and BA was observedto be 2 83 2 90 2 73 and 2 70 times respectively Elongation fell sharply during the firstcycle but it was increased in the subsequent cycles Scanning electron microscope imageswere in different routes and analysis through image analysis software indicated that theequiaxial and shallower dimples were made by increasing the number of cycles at eachroute This showed that the samples were greater in ductility and softness also the meandiameter was the highest in route C and the lowest in route A According to the resultsobtained by the conducted tests route C was selected as the best in terms of mechanicalproperties Keywords Commercial pure aluminum severe plastic deformation Accumulative RollBonding process cross roll accumulative roll bonding Bauschinger effect mechanicalproperties and microstructure

محمدرضا طرقي نژاد

حسين ادريس، احمدرضاييان