Investigation of Copper Foil Thinning Behavior by Flexible-Pad Laser Shock Forming

Abstract:

This paper reports on a novel microforming technique, Flexible-Pad Laser Shock Forming (FPLSF) which uses laser-induced shock waves and a flexible pad to induce plastic deformation on metallic foils. Thickness distribution at the cross-section of the craters formed by FPLSF is analyzed experimentally with respect to laser fluence, which is a significant process variable that controls the deformation pressure. Furthermore, hardness of the deformed samples at the cross-section is measured by nanoindentation testing. It is found that the thinning of copper foil by FPLSF ranges from 7% to 25% for laser fluence ranging between 7.3 J/cm² and 20.9 J/cm². Thinning is maximum at the crater center, which can be attributed to the maximum compressive stresses in the thickness direction, and minimum at the edge portions. With increase in laser fluence, thinning of the foil increases whereas minimum change in hardness is observed. The variation in thinning across different crater locations ranges between 6% and 8% only, which indicates that FDLSF can be developed as a competitive technique to produce components with uniform thickness distribution.

• Periodical: Key Engineering Materials (Volumes 535-536)
• Pages: 306-309
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.535-536.306
• Online since: January 2013
• Authors: Balasubramanian Nagarajan, Sylvie Castagne, Zhong Ke Wang
• Keywords: Flexible-Pad Forming, Laser Shock-Induced Plastic Deformation, Micro-Forming, Thinning

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