پديد آورنده :
امراللهي، رسول
عنوان :
بررسي تجربي رفتارهاي آلياژ حافظه دار فرومغناطيس
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
طراحي كاربردي
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مكانيك
صفحه شمار :
دوازده،84ص.: مصور،جدول،نمودار
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
محمود كدخدائي
استاد مشاور :
پرويز كاملي
توصيفگر ها :
نيكل-منگنز-گاليم , بارگذاري ناقص , خاصيت سوپرالاستيك , نرخ كرنش
تاريخ نمايه سازي :
29/2/92
استاد داور :
محسن بدرسماي، رضا تيكني
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
Experimental Investigation on Behaviors of a Ferromagnetic Shape Memory Alloy Rasoul Amrollahipour r amrollahipour@me iut ac ir 21st January 2013 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Mahmoud Kadkhodaei kadkhodaei@cc iut ac ir Abstract Magnetic shape memory properties of Ni Mn Ga single crystals were characterized by measurement of stress induced martensite reorientation under constant magnetic fields Also magnetic field induced strain as a function of the applied magnetic field under different constant compressive stress levels was investigated All the experiments were performed at room temperature in which the sample is in its martensite phase Compressive stress and magnetic field were applied perpendicular to each other and strain was measured along the compressive load axis For the magneto mechanical characterization two new setups were designed and manufactured The first setup consisted of two permanent magnets which were mounted in parallel with a certain distance from each other depending on the desired amount of the magnetic field These two magnets were able to generate a uniform magnetic field of up to 5 kG at the region connecting the center of the magnets Prior to the experiments this setup was calibrated For this purpose magnetic field strength was measured for several distances The second setup was used to generate a constant compressive stress for the case of varying magnetic fields The specimen was gripped between a fixed end plate and a vertically moveable push rod both of which were made of nonmagnetic steel Some weights were placed on the push rod to apply a constant stress to the sample Magnetoelasticity martensite reorientation shape memory effect and pseudoelasticity were observed throughout the experiments The blocking stress and the twinning stress were found based on the MFIS under a constant compressive stress The maximum MFIS was found to be between 5 7 and 5 9 in various experiments This is close to 6 which is the theoretical maximum reorientation strain for 5M Ni Mn Ga single crystals By increasing the constant compressive stress the maximum MFIS decreases while the critical field magnitude for the start of reorientation increases In order to investigate the behaviors of the sample under incomplete loading unloading cycles the behaviors of the sample under partial loading unloadings were studied The partial loading curves do not matches the curve of the full cycle at an incomplete unloading In other words stress values at partial loadings are less than those at complete loadings At last the effect of strain rate on the stress strain behavior is experimentally studied for Ni Mn Ga single crystals For this purpose the sample was tested under different strain rates The results show that the strain rate has no considerable effect on stress strain behavior of the sample Keyword Ferromagnetic Shape Memory Alloy FSMA Ni Mn Ga Incompelete Loading Pseudoelasticity Strain Rate
استاد راهنما :
محمود كدخدائي
استاد مشاور :
پرويز كاملي
استاد داور :
محسن بدرسماي، رضا تيكني
