Skip to main content
main-content

Tipp

Weitere Artikel dieser Ausgabe durch Wischen aufrufen

11.02.2020 | Original Paper

Effects of continuous cooling rate on morphology of granular bainite in pipeline steels

Zeitschrift:
Journal of Iron and Steel Research International
Autoren:
Shu-jun Jia, Ba Li, Qing-you Liu, Yi Ren, Shuai Zhang, Hong Gao

Abstract

The morphology and characteristics of granular bainite (GB) in pipeline steels at different continuous cooling rates were investigated by scanning electron microscopy, transmission electron microscopy and electron back-scattered diffraction (EBSD). The results show that the morphology of ferrite matrix in GB turned from the lath sheaf structure into the nearly equiaxed large grain with the cooling rate decreasing from high (60 °C/s) to low (5–10 °C/s). At the medium cooling rate (20–40 °C/s), GB consisted of the irregular ferrite matrix, the granular martensite/austenite (M/A) constituents and abundant substructures inside. The formation of the irregular ferrite and substructure was attributed to the high-temperature recovery which occurred at relatively high-temperature stage before phase transformation. The granular morphology of M/A constituents was formed from the carbon-rich triple junctions which were produced by the multidirectional substructure interfaces converged with each other. Particularly, some martensite in M/A constituents was misoriented from the adjacent ferrite by very small misorientation angle, which could be characterized by the mean band contrast function of EBSD qualitatively or semiquantitatively.

Bitte loggen Sie sich ein, um Zugang zu diesem Inhalt zu erhalten

Literatur
Über diesen Artikel

Premium Partner

    Marktübersichten

    Die im Laufe eines Jahres in der „adhäsion“ veröffentlichten Marktübersichten helfen Anwendern verschiedenster Branchen, sich einen gezielten Überblick über Lieferantenangebote zu verschaffen. 

    Bildnachweise