مشخصات پژوهش

عنوان	Effect of Nb on Microstructures and Mechanical Properties of an Ultrafine- Grained Dual Phase Steel
نوع پژوهش	مقاله چاپ‌شده در مجلات علمی
کلیدواژه‌ها	dual phase steels, grain refinement, Nb microalloying element, thermomechanical processing
چکیده	The effect of Nb addition from 0.06 to 0.18 wt.% on microstructural evolutions, mechanical properties, strain-hardening behavior, and fracture mechanism of an ultrafine-grained dual phase (UFG-DP) steel was investigated. The DP steels were cold rolled up to 80% thickness reduction followed by intercritical annealing at 770 C for 6 min to form the UFG structures. Results showed that increasing Nb content up to 0.12 wt.% increased the volume fraction of martensite and decreased the average grain size of ferrite; however, lower martensite content with no further grain refinement was detected in the steel containing 0.18 wt.% Nb. The variations of strength, elongation, strain-hardening exponent, and fracture behavior of the Nb-bearing UFG-DP specimens were explained in terms of the microstructural features. The UFG-DP steel containing 0.12 wt.% Nb showed a superior strength-elongation balance (UTS3UE116 MPa) compared to both the as-received ferritic-pearlitic and the commercially used DP980 steels.
پژوهشگران	علی قاطعی کلاشمی (نفر اول)، احمد کرمانپور (نفر دوم)، عباس نجفی زاده (نفر سوم)، یوسف مظاهری رودبالی (نفر چهارم)