Development of high-carbon low-alloy steel (BW BL 50CRMO4) at Arcelormittal Tubarão and Waelzholz Brasmetal rolling for final application in chainsaw bars
Henrique Severiano de Jesus; Fernando Generoso Neiva Ferreira; Eduardo Alves Machado; Fabiano Almir Barbosa; Juliano Braz Possati; Marcelo Urdapilleta Rodrigues; Maurício Franco Bomfim; Marina de Lima Barroso; Daniel Augusto Ferro; Thomas Frank
Abstract
Over several decades, the industry has been constantly evolving in its manufacturing processes, with optimized and automated equipment ensuring greater stability. New alternatives are continually being proposed to reduce costs and improve competitiveness. This study presents the development of high-carbon low-alloy steel, BW BL 50CrMo4, at ArcelorMittal Tubarão and Brasmetal Waelzholz, as a re-rolled product to meet the demands of the chainsaw bar and tool market, providing a ready-to-use product and reducing the final customer’s heat treatment steps. The production of this type of steel requires rigorous process control from the steel mill to re-rolling. These steels are widely used in components that require high mechanical strength, clarity, shape maintenance, and abrasion resistance. This study investigated, on an industrial scale, the process parameters and critical characteristics for developing a high-carbon steel sheet with Cr and Mo alloy for chainsaw bars. The steel was characterized throughout the entire process (casting, hot rolling, cold rolling + batch annealing, and heat treatment) using tensile testing, hardness testing, optical microscopy (OM), and scanning electron microscopy (SEM). The results showed the evolution of the material’s microstructure, from a ferrite/pearlite microstructure in the hot band, spheroidized in cold rolling/annealing, to a fully bainitic microstructure after austempering, ready for the manufacture of chainsaw bars.
Keywords
References
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Submitted date:
11/01/2024
Accepted date:
01/28/2025
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