Double pulse laser ablation; Laser induced phase explosion; Plasma expansion; Pre plasma formation; Single pulse laser ablation; Water interaction ambient;INDUCED BREAKDOWN SPECTROSCOPY; PHASE-EXPLOSION; NANOSECOND; METALS; PLASMA; ENHANCEMENT; THRESHOLDS

In this paper, single pulse and double pulse laser ablation of an aluminum target in two interaction ambient was investigated experimentally. The interaction was performed by nanosecond Nd:YAG laser beam in air and four depths (i.e. 9, 13, 17, and 21 mm) of distilled water ambient. The irradiation was carried out in single and collinear double pulse configurations in both air and liquid ambient. Crater geometry (depth and diameter) was measured by an optical microscope. The results indicated that the crater geometry strongly depends on both single pulse and double pulse configurations and interaction ambient. In single pulse regime, the crater diameter is higher for all water depths compared to that of air. However, the crater depth, depend on water depth, is higher or lower than the crater depth in air. In double pulse laser ablation, there are greater values for both crater diameters and crater depths in the water. (C) 2016 Elsevier B.V. All rights reserved.