پديد آورنده :
صادقيان، زهره
عنوان :
توسعه كامپوزيت هاي Al- TiB2 نانو ساختار با روش آلياژسازي مكانيكي، سينتر پلاسمايي جرقه اي و اكستروژن گرم
مقطع تحصيلي :
كارشناسي ارشد
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد
صفحه شمار :
پانزده،،[137]ص.: مصور،جدول،نمودار
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
محمد حسين عنايتي
توصيفگر ها :
نانوكامپوزيت , آناليز حرارتي , سختي سنجي , خواص كششي
تاريخ نمايه سازي :
25/7/88
استاد داور :
كمال جانقربان، محمد محسن مشكسار، مهدي احمديان
كد ايرانداك :
ID251 دكتري
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
141 Development of Al TiB2 Nanostructured Composite Using Mechanical Alloying Spark Plasma Sintering and Hot Extrusion Zohreh Sadeghian zsadeghian@ma iut ac ir September 07 2009 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Supervisor Assoc Prof M H Enayati ena78@cc iut ac ir69 Advisor Prof P Beiss70 Department Graduate Coordinator Assoc Prof M Shamanian1AbstractProduction of in situ Al TiB2 nanocomposite powder was studied by using mechanicalalloying MA of pure Ti B and Al powder mixture in a planetary ball mill A double stepprocess was proposed to prevent the formation of undesirable phases such as Al3Tiintermetallic compound The prepared Al TiB2 powder was consolidated by spark plasmasintering SPS followed by hot extrusion with a pre heating temperature of 400 C Two Almatrix composites containing 10 and 20 wt TiB2 were studied to evaluate the effect of TiB2content on mechanical behavior The structural characteristics of powder particles and consolidated samples were studied by X ray diffractometry XRD scanning electron microscopy SEM and conventional and highresolution transmission electron microscopy TEM Differential scanning calorimetery DSC was used to study the stability of powders at high temperatures Hardness and tensile behaviorof extruded samples was also evaluated The results showed that the double step MA process leads to the in situ formation of TiB2particles in the Al matrix with a fine and uniform distribution The resulting composite powdershowed phase stability at high temperatures so that no undesirable phase such as Al3Ti wasidentified in the annealed powder as well as extruded samples The TiB2 particles size in as milled Al 20wt TiB2 powder ranged from10 nm to 1 m although most of them were smallerthan 100 nm Hot extrusion did not increase the TiB2 particles size significantly Furthermorethe average Al grains in the as milled powder was measured to be 15 nm which increased to35 nm after hot extrusion These results show that the prepared Al 20wt TiB2nanocomposite has good thermal stability against grain growth and particle coarsening Extruded Al 20wt TiB2 showed a hardness value of 180 VHN and yield and tensile strengthof 480 and 540 MPa respectively which are much higher than those reported for similarcomposites made by other processes In addition mechanical properties showed no drasticaldecrease up to 300 C Key Words in situ Al TiB2 nanocomposite mechanical alloying SPS Hot extrusion69 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran70 Institute for Materials Applications in Mechanical Engineering RWTH Aachen University Germany
استاد راهنما :
محمد حسين عنايتي
استاد داور :
كمال جانقربان، محمد محسن مشكسار، مهدي احمديان
