نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی کارشناسی ارشد شناسایی و انتخاب مواد مهندسی ، دانشکده مهندسی مواد و متالورژی، دانشگاه علم و صنعت ایران، تهران، ایران
2 استاد/دانشکده مهندسی مواد و متالورژی دانشگاه علم و صنعت ایران
3 هیات علمی دانشکده مواد- دانشگاه علم و صنعت ایران
4 دانشکده مهندسی مواد و متالورژی، دانشگاه اراک،اراک،ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
In this study, the effect of temperature on the kinetics of austenite to martensite transformation and the tensile properties of 304 austenitic stainless steel were investigated. In order to achieve this goal, uniaxial tensile tests were performed on 304 austenitic stainless steel samples at two temperatures of 25 and -78 . Microstructural investigations were conducted using an optical microscope and a ferritscope. According to the results, the volume fraction of martensite at -78 temperature is approximately 13 higher than at 25 due to lower stability of austenite and increased driving force for the transformation of austenite into martensite. At temperatures 25 and -78 , the maximum transformation rate of austenite to martensite was obtained at true strains of 0.3 and 0.2, respectively, and the comparison of these results indicated that at the temperature of -78 , there was a greater transformation rate than at 25 . The work hardening rate graphs for uniaxial tensile testing were plotted at two temperatures of 25 and -78 . A higher work hardening rate was observed at -78°C than at 25°C, and the strength coefficients and work hardening exponents of the austenite and martensite phases increased as temperature was decreased. In addition, in the uniaxial tensile test, the average hardness was determined at -78 and 25 as 309 and 280, respectively.
کلیدواژه‌ها [English]
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