Effects of Rolling Temperature on the Microstructure and Mechanical Properties in an Ultrafine‐Grained Low‐Carbon Steel

Abstract

Ultrafine grained low‐carbon steels are fabricated by cryorolling and cold‐rolling martensite starting microstructure at liquid nitrogen temperature and ambient temperature, respectively. The results indicate that cryorolling process at liquid nitrogen temperature present more potential in refining ferrite grains in low‐carbon steel (132 nm) than ambient temperature deformation (330 nm). The tensile strength increase from 867.0 to 970.2 MPa for the specimen cryorolled at liquid nitrogen temperature compared to the specimen rolled at ambient temperature. The decreased elongation in the specimen at liquid nitrogen temperature is attributed to the coarse Fe3C particles during the annealing. Moreover, Fe3C particles precipitate during the cold‐rolling and subsequent annealing processes in the cold‐rolled specimen, while Fe3C particles in the cryorolled specimen are mainly formed during the annealing process due to the suppression of diffusion of carbon atoms during the cryorolling process.

Effects of Q&T parameters on phase transformation, microstructure, precipitation and mechanical properties in a PS-30Cr2Nb pipeline steel

“…Specimens for precipitations observation by TEM were prepared by carbon replica. Related methods for laboratory sample preparation were given in author's previous studies [23][24][25]. Besides, Adobe Photoshop 2013 was used to characterize the grains in the obtained microstructures.…”

Study on the mechanical properties, wear resistance and microstructure of nano-SiCp/ZA38 composite material under the synergistic effects of thermal-force-acoustic field

“…Metallographic specimens were prepared for observing the as-cast microstructure and fracture morphology of specimens treated by different processing parameters. Related metallographic preparation methods have been previously described [26][27][28][29][30]. A ZEISS optical microscope (OM) and a field-emission scanning electron microscope (FE-SEM) with an energy dispersive spectroscopy (EDS) were used for the studies.…”

Influences of Quenching Temperature on the Microstructure Evolution and Strength−Toughness of a Novel Medium‐Carbon Ti−Mo‐Bearing Martensite Steel

“…The detailed descriptions of sample preparations are presented in the literature. [10][11][12]25,27] 3. Results…”

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