Abstract
In laser forming, thermally induced strains transverse to the laser scan line vary with depth in the material and contribute most significantly to the desired deformation. The through-thickness transverse residual strain distribution was measured by neutron diffraction in laser-formed low carbon steel and aluminium alloy specimens. The specimens were formed with a wide range of laser line energies covering the temperature gradient mechanism (TGM) and shortening or upsetting mechanism (SM), and for single and multi-pass forming (up to 3 laser passes). Below the saturation line energy where the TGM dominates, the gradient of the through-thickness strain distribution was found to increase with increasing line energy and number of laser passes; the gradient decreased again at line energies above the saturation line energy where the efficiency of the TGM decreases. Iterative laser forming can be applied to reduce weld-induced distortions. The peak longitudinal strain measured in the weld seam of a specimen that had been straightened by iterative laser forming was also significantly reduced. (C) 2011 Elsevier B.V. All rights reserved.
Original language | English |
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Pages (from-to) | 90-99 |
Number of pages | 10 |
Journal | Journal of Materials Processing Technology |
Volume | 212 |
Issue number | 1 |
DOIs | |
Publication status | Published - Jan 2012 |
Keywords
- Iterative laser forming
- Iterative laser bending
- Iterative laser straightening
- Residual strain
- Neutron diffraction
- Weld distortion