Abstract
The aimed study proposes laser shock peening without a coating of high strength ultrafine bainitic steel to mitigating the fatigue failures for automotive and structural engineering applications. Laser pulse density of 2500 pulses/cm2 (75% overlapping) was optimised based on the induced residual stresses for employing the wide range of characterisations. The roughness and topographic results showed that surface roughening was controlled by tuning the laser pulse density. The High-Resolution X-ray Diffraction analysis confirmed the lattice misorientation resulting peak shift and the trend towards martensite phase transformations. The electron microscopic micro/nanostructure analyses revealed the grain refinement features such as nano-twins, micro shear bands and shear cells. The work hardening depth analysis indicates the significant enhancement in the mechanical properties. Completely reversed (R = −1) high-cycle fatigue tests extended the lifespan by an average of five times than the untreated. Also, it has potential to repair the structural components effectively.
Original language | English |
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Pages (from-to) | 447-458 |
Number of pages | 12 |
Journal | Optics and Laser Technology |
Volume | 115 |
Early online date | 4 Mar 2019 |
DOIs | |
Publication status | Published - 1 Jul 2019 |
Bibliographical note
NOTICE: this is the author’s version of a work that was accepted for publication in Optics and Laser Technology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Optics and Laser Technology, 115, (2019)DOI: 10.1016/j.optlastec.2019.02.041
© 2019, Elsevier. Licensed under the Creative Commons Attribution-NonCommercialNoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Keywords
- Bainitic ferrites
- Fatigue
- Hardness
- Laser shock peening (LSP)
- Plastic deformation
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering