FABRICATION AND CHARACTERIZATION OF MICRO DENT ARRAY PRODUCED BY LASER SHOCK PEENING ON ALUMINUM SURFACES

摘要

Surface micro dents may act as lubricant reservoirs to reduce friction and wear in sliding and rolling contact applications. Surface patterning has become a valuable technique for fabricating micro dents. Alternative methods such as micromachining present obvious limitations in comparison with laser shock peening (LSP). In this paper, the use of LSP along with an automatic X-Y table proves to be an attractive and reliable method for producing micro dent arrays with enhanced surface integrity and free of cracks. Surface topography and microhardness of the fabricated micro dent arrays on polished aluminum 6061-T6 have been characterized. It was found that low laser power produced deep micro dents. The hardness increased approximately 55% from the bulk material due to LSP induced strain and strain rate hardening.