Product Code: ICAL08_1903

Development of Indirect Laser Peening for Forming a Micro-dimple and Making Powder Deposition on the Substrate
Authors:
Muneharu Kutsuna, Retired; Aichi-ken Japan
Haruki Mizutani, Nagoya University; Nagoya Japan
Hiroki Inoue, Nagoya University; Nagoya Japan
Presented at ICALEO 2008

A modification of laser peening has been carried out for forming a micro-dimple and introducing compressive residual stress in the materials and making powder deposition on the surface of substrates such as metal, wood and polymer using a metal foil. In the present work, Q-switch YAG laser with a max. pulse energy of 650mJ as a wave length of 532nm was used to generate high plasma pressure of around 5GPa in 10-20ns. The diameter and depth of dimple formed can be controlled by the beam spot size, max.
pulse energy and thickness of metal foil in the diameter range of 200μ 2000μ and the depth range of 5 100μ. A trial of indirect laser peening was carried out to make MoS2 powder deposition on aluminum alloy substrate to reduce the friction energy loss of piston. Process parameters have been investigated to characterize this new process. The characteristics of indirect laser peening has been investigated by measuring the residual stress of the specimens and the hardness change.