9106

8444

كارشناسي ارشد

شناسايي و انتخاب مواد

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد

1392

يازده،74ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

مرتضي شمعانيان، حميدرضا سليمي جزي

محمدرضا طرقي ن‍‍ژاد

16/4/93

محمدحسين عنايتي، احمد رضاييان

مهندسي مواد

ID8444

76 Joining of Al AI2O3 nanostructured metal matrix composite by Transient Liquid Phase Mona Yarahmadi m yarahmadi@ma iut ac ir January 21 2014 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisors Dr Morteza Shamanian Prof E mail shamanian@cc iut ac irDr Hamid Reza Salimi Jazi Assis Prof E mail hrjazi@cc iut ac irAbstractTodays nano structure aluminum matrix composites are widely used in many industrial applications due totheir superior properties such as high strength to weight ratio However joining problems of these compositematerials is a challenge which limits their applications Mechanism of a nanostructured sheet of metal matrixcomposite of Al Al2O3 reinforced by micro metric alumina particles was investigated Transient liquid phase TLP diffusion bonding method was used as the joining and the effects bonding temperature and time on thejoint properties were investigated Nanostructured sheet samples of Al 5wt Al2O3 were produced byaccumulative roll bonding ARB and a thin interlayer of pure copper was deposited on one side joiningsurface by electro deposition technique Optical microscopy and scanning electron microscopy SEM wereused to investigate the structure of sheet components bonded interfaces and joint fracture surfaces atdifferent conditions X ray diffraction patterns were utilizied to investigate the aluminum crystallite size inthe nanostructured sheet components The average size of grain was about 92 nm Then were no significantchanges in the crystallite size during TLP bonding Consternation of alumina particles micro cracks andporosity were found in the joint areas that were filled from Al solid phase and fine CuAl2 precipitatedparticles The filled areas increased as the joint temperature increase It is due to a higher amount of themolten material produced during joining Moreover the amount of CuAl2 precipitated particles reduced asthe joining temperature increased resulting in reduction of the hardness of the Al solid phase in the jointarea The shear strength of the bonded joints was also evaluated using a tension test system The maximumshear strength 82 of the base metal shear strength was achieved at the bonding temperature of 590 C andprocess duration of 30 minutes Analysis of the fractured surfaces showed plastic deformation shear dimplesand partially ductile failure Some alumina particles were observed on the fractured surface At low joiningtemperatures the joint strength improved by incresing bonding time whiles at high joining temperatures thejoint strength decreased due to reduction of CuAl2 particles in the Al solid phase Keywords Nanostructure Transient liquid phase Interlayer Accumulative rolls bonding Isothermalsolidification

مرتضي شمعانيان، حميدرضا سليمي جزي

محمدرضا طرقي ن‍‍ژاد

محمدحسين عنايتي، احمد رضاييان