Abstract For dismantling nuclear power plants, an underwater cutting study was conducted using a high power fiber laser. With a laser power of 9 kW, cutting tests were performed on stainless steel with a thickness of 50–100 mm. For this study, a waterproof cutting head consisting of a focusing element with a long focal length of 600 mm and a supersonic nozzle was used for high cutting efficiency. For thicknesses of 70 mm or less, it was possible to cut only with a single supersonic nozzle, while for a thickness of 80 mm or more, an initially pierced specimen or a double nozzle was required for successful cutting. Through these techniques, we were able to perform the cutting underwater up to a thickness of 100 mm. Furthermore, the kerf widths were as small as 1–2 mm, the amount of secondary waste will likely be small, which will reduce waste disposal costs.

中文翻译：

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水下激光切割最厚 100 毫米的不锈钢，用于核电站的拆除应用

摘要 为了拆除核电站，使用高功率光纤激光器进行了水下切割研究。激光功率为 9 kW，对厚度为 50-100 mm 的不锈钢进行切割试验。在这项研究中，防水切割头由一个长焦距为 600 mm 的聚焦元件和一个超音速喷嘴组成，用于实现高切割效率。对于 70 毫米或更小的厚度，可以仅使用单个超声速喷嘴进行切割，而对于 80 毫米或更大的厚度，成功切割需要最初刺穿的样品或双喷嘴。通过这些技术，我们能够在水下进行厚度达 100 毫米的切割。此外，切口宽度小至 1-2 毫米，二次废物的数量可能很小，