PSI - Issue 3

Jesús Toribio et al. / Procedia Structural Integrity 3 (2017) 3–10 Author name / Structural Integrity Procedia 00 (2017) 000–000

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3. Microstructure evolution during cold drawing The microstructural evolution of pearlitic microstructures during cold drawing has been extensively studied in the past, from the classical studies performed by Embury and Fisher (1966) and Langford (1977) about drawing and deformation of pearlite, to the review of data on the interlamellar spacing published by Ridley (1984) or the study performed by Zelin (2002) of microstructure evolution in pearlitic steels during wire drawing. Specific analyses by Toribio and Ovejero (1997, 1998a, 1998b, 1998c) demonstrate the progressive slenderizing and orientation (in the wire axis or cold drawing direction) of the pearlitic colonies (first microstructural level), as well as increasing orientation and densification of the ferrite/cementite lamellae (second microstructural level) linked with a decrease of pearlite (ferrite/cementite) interlamellar spacing. Thus the microstructure of the cold-drawn pearlitic steel wires becomes progressively oriented as the cold-drawing degree increases. A recent systematic compendium containing detailed information about microstructural evolution in cold-drawn pearltic steel was recently published by Toribio et al. (2016). Figs. 3 shows the microstructures of progressively drawn pearlitic steels in longitudinal (left) and transverse (right) sections.

Fig. 3. Microstructures of progressively cold-drawn pearlitic steels in longitudinal (left) and transverse (right) sections for steels that have undergone 0 (top) 3 (middle) and 6 (bottom) steps of cold drawing.