Modelling Machining-Induced Residual Stresses after Laser-Assisted Turning of Steels

Abstract:

The current study examines the effects of laser assistance on machining-induced residual stresses (RS), using finite element modelling, during turning of steels. Dry orthogonal cutting was modelled, along with the pre-heating effect of the laser beam. AISI 4340 steel was used in the current work. Laser-assisted machining (LAM) resulted in higher surface tensile RS compared to conventional machining, with more pronounced effects at lower feed rates. This is basically because the assisted material experienced higher plastic deformation, due to thermal softening, as well as higher temperatures, which are both attributed to the pre-heating effect of LAM.

• Periodical: Advanced Materials Research (Volume 996)
• Pages: 622-627
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.996.622
• Online since: August 2014
• Authors: Mohamed N.A. Nasr*, Mohamed Balbaa, Hassan Elgamal
• Keywords: Finite Element Modeling (FEM), Laser-Assisted Machining (LAM), Residual Stress

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