Abstract
Laser cutting is widely used in the metal industry, particularly when components of high strength steel sheets are produced. However, the roughness of cut edges produced by laser differs from that obtained by other methods, such as mechanical blanking, and this fact influences the fatigue performance. In the present investigation, specimens of two grades of high strength austenitic steels, i. e. AISI 301LN and TWIP17Mn, were cut by laser and tested in the high cycle fatigue regime to determine their corresponding fatigue limits. A series of fatigue specimens were tested without polishing and other series after a careful polishing of the cut edges, in order to assess the influence of the cut edges condition. Results indicate a significant influence of the edge roughness, more distinctive for AISI 301LN than for TWIP steel.
Kurzfassung
Laserschneiden wird breitflächig in der metallverarbeitenden Industrie angewendet, insbesondere wenn Komponenten aus hochfesten Stählen gefertigt werden. Allerdings differiert die Rauheit der mittels Laser produzierten Schnittkanten zu denen, die mit anderen Verfahren, wie beispielsweise dem mechanischen Stanzen, hergestellt werden, was wiederum die Performanz unter Ermüdungsbeanspruchung beeinflusst. In der vorliegenden Untersuchung wurden Proben von zwei hochfesten austenitischen Stählen, AISI 301LN und TWIP17Mn, mit Laser geschnitten und im High-Cycle-Regime ohne Polieren der Schnittkanten geprüft, sowie eine andere Serie nach sorgfältigem Polieren, um den Einfluss der Schnittkantenbedingungen abzuschätzen. Die Ergebnisse deuten einen signifikanten Einfluss der Kantenrauheit an, der für AISI 301 LN stärker ausgeprägt ist als für den TWIP Stahl.
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