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Apparent spot in circular laser hardening: effect of process parameters

  • Non-conventional processes: L. Santo
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Abstract

Back tempering, a well known problem in laser hardening of steels, occurs when a large area is hardened by multiple overlapping passes. The overlapping passes partially temper the previous hardened material in the overlapped zone. Back tempering also occurs in circular laser hardening, a typical laser surface treatment used in case of cylindrical workpieces, since the treated starting/ending surfaces are slightly overlapped. In order to avoid the back tempering phenomenon the apparent spot (AS) technique is addressed and investigated. In case of circular laser hardening the AS technique is based on imposing a high rotational speed to the workpiece, since an apparent circular spot is generated, which contemporaneously heats all the annular surface of the workpiece. As a consequence, back-tempering is avoided. In this paper an experimental campaign is deigned to analyze the effects of the process parameters (laser power, workpiece rotational speed and workpiece diameter) on the hardened tracks in terms of width, thickness and hardness values, when the AS is applied to the circular laser hardening.

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Authors and Affiliations

  1. Department of Mechanical and Industrial Engineering, University of Brescia, Brescia, Italy

    L. Giorleo

  2. Department of Mechanical Engineering, Politecnico di Milano, Viale la Masa 1, 20159, Milano, Italy

    A. Liu & B. Previtali

Authors
  1. L. Giorleo
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  2. A. Liu
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  3. B. Previtali
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Correspondence to A. Liu.

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Giorleo, L., Liu, A. & Previtali, B. Apparent spot in circular laser hardening: effect of process parameters. Int J Mater Form 3 (Suppl 1), 1119–1122 (2010). https://doi.org/10.1007/s12289-010-0968-9

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  • DOI: https://doi.org/10.1007/s12289-010-0968-9

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