Microstructure evolution and adiabatic heating during dynamic biaxial deformation of a 304 stainless steel

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:793

Article

Xia, Peikang^1,2  Canillas Rodriguez, Francisco Javier²  Sabirov, Ilchat¹ 

[1] IMDEA Mat Inst, Calle Eric Kandel 2, Madrid 28906, Spain

[2] Univ Politecn Madrid, ETS Ingenieros Caminos, Madrid 28040, Spain

关键词: 304 stainless steel;    Dynamic deformation;    Biaxial stress;    Adiabatic heating;    Martensite transformation;   

DOI  :  10.1016/j.msea.2020.139829

来源: Elsevier

【 摘 要 】

This study focuses on the microstructure evolution and adiabatic heating during high strain rate biaxial deformation of a 304 stainless steel. Adiabatic heating is measured in situ during drop weight impact testing of the studied material. The considerable temperature rise induced by adiabatic heating (up to 184.3 degrees C when impacted with 140 J) is detected. The microstructure was analyzed by X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and high resolution transmission electron microscopy (HRTEM) techniques. Dislocation glide, twinning and austenite-martensite phase transformation are operating during high strain rate plastic deformation. The XRD analysis shows a steady increase of alpha'-martensite fraction (up to 36%) with plastic strain (up to 0.8), whereas the fraction of intermediate epsilon-martensite remains negligible (<0.5%). The biaxial stress compensated the possible impediment of martensitic transformation caused by adiabatic heating and the increasing stacking fault energy (SFE). Nanotwins having a width of similar to 5 nm-similar to 20 nm are inhomogeneously distributed in the microstructure. Interrelationship between adiabatic heating, deformation mechanisms and microstructure evolution is discussed.

【 授权许可】

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