عنوان :
سنتز و مشخصه يابي نانو كامپوزيت پايه سراميكي آلومينات مونوكلسيم و بررسي مكانيزم تشكيل آن
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
مهندسي مواد
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد
صفحه شمار :
چهارده، 85ص.: مصور، جدول، نمودار
استاد راهنما :
محمد حسن عباسي، احمد منشي
توصيفگر ها :
فعال سازي مكانيكي , عمليات حرارتي , سينتيك
تاريخ نمايه سازي :
31/2/91
استاد داور :
محمد حسين عنايتي، رحمت ا... عمادي
تاريخ ورود اطلاعات :
1396/10/06
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
86 Synthesis and Characterization of Ceramic Matrix Nanocomposite of Monocalcium Aluminate and Studying the Formation Mechanism Sheida Shiri Email address s shiri@ma iut ac ir Isfahan University of Technology Isfahan 84156 83111 Iran Department of Materials Engineering Language Farsi Degree M Sc Prof Mohammad Hasan Abbasi Supervisor E mail abbasi32@cc iut ac ir Prof Ahmad Monshi Supervisor E mail a monshi@cc iut ac irAbstractMonocalcium aluminate CA is the main constituent of all types of calcium aluminate cements This cementhave unique properties These properties include high temperature and high abrasion resistance andresistance to wide range of chemically aggressive conditions Although CA cement has good properties theamount of undesirable phases and grain growth in these materials result in poor quality in some properties Inrecent years there has been an increasing interest in the synthesis of nanocrystalline CA for improving thesedefects In this research high energy ball milling followed by annealing was used to synthesis CAnanoceramic and CA nanocomposite SiO2 nanoparticles in nano cement base In the first stage high energyball milling followed by annealing was performed on a mixture of CaO and Al2O3 to synthesize CA X RayDiffraction XRD measurments showed that no calcium aluminate was formed during ball milling even after100hr Annealing the powder mixture milled for different times in 900 1000 1200 C showed that thenucleation and growth of CA took place at 1000 C after 2hr Depending on milling time by increasing theannealing temperature the amount of CA increased and also secondary phases apppeared CA single phaseswas obtained on the sample milled for 100hr and fired at 1200 C The average grain size of productsmeasured by scherrer s and modified scherrer s equations was in nanometric range The product wascharacterized with Scanning Electron Microscope SEM and Transmission Electron Microscope TEM TEM results showed that the particle size of products were in the range 40 100nm In the second stage thekinetic of formation of CA have been studied with fitting method and the effect of ball milling on activationenergy was investigated Results showed that the amount of activation energy decreased with increase inmilling time but with increase the milling time from 70hr to 100hr the amount of activation energy didn tchange These results showed that the formation of CA needs high energy ball milling and annealing In thethird stage the hydration characterization of CA was studied with XRD and SEM analysis and influence ofnano SiO2 particles were investigated on mechanical and physical properties The hydration of the cementwith the addition of nano SiO2 particles in 0 5 1 1 5 2 were evaluated at the water cement ratio of 0 3 to1 and was compared with plain cement The experimental results showed that the mechanical and physicalproperties of nanocomposite with the specific amount of nano particles were better than that of a plain concrete Keywords Nanoceramic Monocalcium aluminate Mechanical activation Annealing Kinetic nanocomposite
استاد راهنما :
محمد حسن عباسي، احمد منشي
استاد داور :
محمد حسين عنايتي، رحمت ا... عمادي
