پديد آورنده :
مظاهري رودبالي، يوسف
عنوان :
تحولات ريز ساختاري و خواص مكانيكي فولادهاي دوفازي فوق ريز/ نانو دانه با عمليات ترمومكانيكي
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مواد
صفحه شمار :
پانزده،154ص.: مصور،جدول،نمودار
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
عباس نجفي زاده، احمد كرمانپور
توصيفگر ها :
فرايند ترمو مكانيكي , آنيل بين بحراني , رفتار كرنش سختي , مكانيزم شكست
تاريخ نمايه سازي :
3/12/93
استاد داور :
محمدرضا طرقي نژاد، رامين ابراهيمي، احمد رضائيان
كد ايرانداك :
ID720 دكتري
چكيده انگليسي :
Microstructural evolutions and mechanical properties of ultrafine nano grained dual phase steels by thermomechanical treatment Yousef Mazaheri Roudbali y mazaheri@ma iut ac ir January 17 2015 Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran1st Supervisor Abbas Najafizadeh1 a najafi@cc iut ac ir2ed Supervisor Ahmad Kermanpur2 ahmad k@cc iut ac irAbstractUltrafine grained dual phase UFG DP steels was produced by a new route utilizingsimple cold rolling and subsequent intercritical annealing of ferrite martensite duplexstarting structures The effects of processing parameters such as rolling reduction intercritical annealing temperature and time on the microstructural evaluations andmechanical properties have been studied The ferrite grain size and martensite volumefraction were depended on the thermomechanical processing parameters UFG DP steelswith an average grain size of about 1 2 m and chain networked martensite islands wereachieved by short intercritical annealing of the 80 cold rolled duplex microstructures Itis proposed that complete recrystallization of ferrite before the austenite formation leads toa large extent randomly distributed austenite in the ferrite matrix and chain networkedstructure The strength of the low carbon steel with the new UFG DP microstructure wasreached over 1500 MPa about 200 higher than that of the as received state e g 540MPa without loss of ductility Tensile testing revealed good strength elongation balancefor the new DP steels UTS UE 100 150 J cm 3 in comparison with the previous worksand commercially used high strength steels i e DP600 DP800 and DP980 Keywords Dual phase steel Ultrafine grained Thermomechanical processing Mechanical characterization IntroductionNew materials are constantly being developed to provide desirable properties compared toprevious materials This evolution is usually done by changing in the microstructure of1 Professor Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran 2 Associate Professor Department of Materials Engineering Isfahan University of Technology Isfahan 84156 83111 Iran
استاد راهنما :
عباس نجفي زاده، احمد كرمانپور
استاد داور :
محمدرضا طرقي نژاد، رامين ابراهيمي، احمد رضائيان
