4112

3887

كارشناسي ارشد

شناسايي و انتخاب مواد

اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد

1386

هشت، 95، [II]ص.: مصور، جدول، نمودار

ص.ع. به: فارسي و انگليسي

محمود مرآتيان

مسعود پنجه پور

05/06/87

مسعود امامي، بهزاد نيرومند

مهندسي مواد

ID3887

به فارسي وانگليسي: قابل رؤيت در نسخه ديجيتال

Abstract Aluminum matrix composites have greatly been used in automotive military and aerospace industries because of their high specific strength good wear resistance low coefficient of thermal expansion and high oxidation resistance One of the methods for fabricating aluminum matrix composites is in situ method in which reinforcing phase is formed in matrix phase via chemical reactions between elements or between elements and other compounds In this research mechanically activated aluminum sulfate was injected into molten pure aluminum to produce in situ aluminum alumina p composite Mechanical activation of aluminum sulfate reduced its decomposition temperature from 950 C to aluminum melting point which it was attributed to decrease of crystallite size increase of lattice strain and specific surface area Kinetics of thermal decomposition of aluminum sulfate was studied by thermogravimetric data under non isothermal conditions Although mechanism of decomposition reaction of aluminum sulfate was not changed due to mechanical activation activation energy value was decreased with increasing of activation time Aluminum sulfate was decomposed in melt to alumina and SO3 which later one left the melt without changing its composition Scanning electron microscopy SEM was used to evaluate sizes and distribution of alumina particles in composite samples It was found that distribution of alumina particles was improved with increasing of the rotation speed of impeller and alumina particles size was almost one micron Mechanical properties of fabricated composites were evaluated by hardness wear and tension tests Weight loss of samples after 100 meters wear under 4 Newton load was reduced from 10 1 milligrams for non composite specimen to 5 0 milligrams for composite one Yield stress and ultimate tensile strength of specimens were increased but their elongations were decreased with increased alumina percentages pdfMachine A pdf writer that produces quality PDF files with ease Produce quality PDF files in seconds and preserve the integrity of your original documents Compatible across nearly all Windows platforms if you can print from a windows application you can use pdfMachine Get yours now

محمود مرآتيان

مسعود پنجه پور

مسعود امامي، بهزاد نيرومند