Microstructural Features of Strain-Induced Martensitic Transformation in Medium-Mn Steels with Metastable Retained Austenite/ Cechy Mikrostrukturalne Indukowanej Odkształceniem Przemiany Martenzytycznej W Stalach Sredniomanganowych Z Metastabilnym Austenitem Szczątkowym

Archives of Metallurgy and Materials

A. Kilarski¹  K. Radwanski²  R. Swadzba²  A. Grajcar³ 

[1] GENERAL MOTORS MANUFACTURING POLAND, 1 ADAMA OPLA STR., 44-121 GLIWICE, POLAND;INSTITUTE FOR FERROUS METALLURGY, 12-14 K. MIARKI STR., 44-100 GLIWICE, POLAND;SILESIAN UNIVERSITY OF TECHNOLOGY, INSTITUTE OF ENGINEERING MATERIALS AND BIOMATERIALS, 18A KONARSKIEGO STR., 44-100 GLIWICE, POLAND

关键词: Keywords: multiphase steel;    medium-Mn steel;    TRIP effect;    strain-induced martensite;    retained austenite;    carbide-free bainite;   

DOI  :  10.2478/amm-2014-0283

学科分类：金属与冶金

来源: Akademia Gorniczo-Hutnicza im. Stanislawa Staszica / University of Mining and Metallurgy

【 摘 要 】

The work addresses relationships between the microstructure evolution and mechanical properties of two thermomechanically processed bainitic steels containing 3 and 5% Mn. The steels contain blocky-type and interlath metastable retained austenite embeded between laths of bainitic ferrite. To monitor the transformation behaviour of retained austenite into strain-induced martensite tensile tests were interrupted at 5%, 10%, and rupture strain. The identification of retained austenite and strain-induced martensite was carried out using light microscopy (LM), scanning electron microscopy (SEM) equipped with EBSD (Electron Backscatter Diffraction) and transmission electron microscopy (TEM). The amount of retained austenite was determined by XRD. It was found that the increase of Mn addition from 3 to 5% detrimentally decreases a volume fraction of retained austenite, its carbon content, and ductility.

【 授权许可】

Unknown