Abstract

Underwater laser machining process is an alternative method to cut materials with less thermal damage due to the water cooling of workpiece during the ablation. However, the rapid cooling induced by water can instantly solidify the laser-molten material rather than expel it to form a cut. To understand the roles of processing temperature on ablation performance in water, this paper presents the influences of water temperature on cut width, depth, and surface morphology in the underwater laser grooving of silicon. The effects of laser power, laser traverse speed, and number of laser passes on the groove characteristics were also examined in this work. The results revealed that using high water temperature can increase the groove aspect ratio, particularly when high laser power, slow traverse speed, and multiple laser passes were employed. However, debris deposition and oxides were found on the laser-ablated surface when processing at high water temperature. The implication of this study could enhance the ablation rate for the underwater laser as well as low-power laser cutting systems.

中文翻译：

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在不同温度下激光烧蚀水中的硅

摘要

水下激光加工工艺是一种切削材料的替代方法，该材料由于烧蚀过程中的水冷而具有较小的热损伤。但是，水引起的快速冷却可以立即使激光熔化的材料凝固，而不是将其排出而形成切口。为了了解加工温度对水中切削性能的作用，本文介绍了水温对水下激光开槽硅中的切割宽度，深度和表面形态的影响。在这项工作中，还研究了激光功率，激光移动速度和激光通过次数对沟槽特性的影响。结果表明，使用高水温可以提高凹槽的纵横比，特别是在使用高激光功率，慢速移动速度和多次激光通过的情况下。然而，在高水温下加工时，在激光烧蚀的表面上发现碎屑沉积和氧化物。这项研究的意义可以提高水下激光器以及低功率激光切割系统的烧蚀率。