PSI - Issue 81

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ScienceDirect

Procedia Structural Integrity 81 (2026) 54–57

VIII International Conference “In -service Damage of Materi als: Diagnostics and Prediction” (DMDP 2025) Relationship between anisotropic microstructure and strength in cold drawn pearlitic steel wires with oriented pearlite:

On the validity of the Hall-Petch equation Jesús Toribio*, Beatriz González, Juan-Carlos Matos Fracture & Structural Integrity Research Group (FSIRG), University of Salamanca (USAL) E.P.S., Campus Viriato, Avda. Requejo 33, 49022 Zamora, Spain

© 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2025 organizers Keywords: Pearlitic steel; cold drawing; multiscale microstructural evolution; prior austenite grain; pearlitic colonies; pearlite lamellae. 1. Introduction High-strength prestressing steel wires for civil engineering use in prestressed concrete structures are manufactured by cold drawing a previously hot rolled eutectoid steel bar in several passes to increase the yield strength. The steelmaking process by progressive cold drawing produces important plastic deformations in the material and activates a strain hardening mechanism which is responsible for the extremely high yield strength useful for structural engineering. Abstract This paper studies the relationship between anisotropic microstructure and strength in heavily cold drawn pearlitic steels supplied in the form of prestressing steel wires for prestressed concrete, analyzing the influence of the microstructural changes undergone by eutectoid pearlitic steels during continuous cold drawing on their yield strength. To this end, samples from a real manufacturing process (wire drawing) were studied, and consideration was given to the microstructure evolution as the drawing progresses up to the final commercial product that is heavily drawn and has undergone severe straining. It is seen that the pearlite interlamellar spacing (decreasing with cold drawing) influences clearly the improvement of yield strength (increasing with cold drawing, which is the final aim of manufacturing), although a relationship of the Hall-Petch type cannot be fitted in this case, probably because cold drawing produces not only an increasing closeness of the pearlitic packing, but also a microstructural orientation in the material. To overcome this difficulty, the strength is related to the cumulative plastic strain after cold drawing by means of the Embury-Fisher equation, and also by a modified Hall-Petch expression, where to calculate the distance between barriers against dislocational movement one must consider, apart from the average interlamellar spacing, the average orientation angle.

* Corresponding author. Tel.: +34-677566723; fax: +34-980545002. E-mail address: toribio@usal.es

2452-3216 © 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2025 organizers 10.1016/j.prostr.2026.03.010