الفهرس 
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Abstract
Austenitic stainless steels form the second generation of advanced high strength steels (AHSS). They are known for combining high strength with ductility. High manganese austenitic stainless steels with nitrogen additions are being used to avoid nickel and its related issues. The aim of this thesis is to design, produce and investigate a series of high manganese austenitic stainless steel with carbon and nitrogen addition and low nickel content. The theoretical part of this study discusses different types of high manganese steels and stainless steels. Stacking fault energy (SFE) was studied extensively. The effects of different parameters on stacking fault energy and the consequent effect on deformation mechanisms were explored. Different methods for stacking fault energy calculation and measurement were approached. A thermodynamic model was used for stacking fault energy calculation for alloy design step. Three different alloys were produced using an air induction furnace. The produced alloys underwent hot forging, hot and cold rolling and heat treatments. The resulting microstructures were studied by optical metallography, X-ray diffraction and scan electron microscope (SEM) equipped with electron backscatter diffraction (EBSD) technique. Hardness tests, tensile tests and electrochemical polarization tests were used to investigate mechanical and corrosion properties. The results indicate that thermodynamic modeling of SFE is a valid approach. The produced alloys showed an austenite microstructure. EBSD imaging of tensile tested specimen exhibited twinning as a secondary deformation mechanism. The different produced conditions showed superior strength with a maximum of 1.43 Gpa, ductility with a maximum of 65% and good corrosion resistance.