激光焊技术在核电站水下部件维修的应用分析

Analysis of the application of laser welding technology in maintenance of the underwater components of nuclear power station

材料受到辐照等因素影响会发生劣化、脆化,核电站水下部件长期使用后存在发生早期失效的风险。激光焊技术具有焊接质量高、污染少等优点,在核电站水下部件维修中具有良好的应用前景。文中对比分析了目前水下激光焊2种主要工艺,水下湿法激光焊和水下局部干法激光焊。结果显示:激光光束受到水体衰减、气泡反射等多种因素影响,水下湿法激光焊很难获得高质量焊缝;水下局部干法激光焊能够获得质量优良的焊接接头,成为当下研究热点和主要方向,获得稳定的水下气室和全熔透焊缝背面焊缝保护是水下局部干法激光焊焊接工艺需要解决的主要问题。进一步以水下激光焊接为关键词在国际某著名研究平台上进行检索发现:水下激光焊接技术已经走出试验室向工程应用发展,而更深入的理论研究也在积极同步开展,其研究方向很可能是皮秒、飞秒激光。

This paper put its eyes on the PWR's underwater components which have the risk of early failure after long-term in-service because the material tends to deteriorate and embrittle due to irradiation and other factors,and should be maintenanced.In this paper,two main technologies used as underwater welding were contrastively analyzed,named underwater wet laser welding and underwater local dry laser welding.It is difficult to obtain high quality weld by underwater wet laser welding for the reason of some disadvantages on laser beam underwater,such as water attenuation,bubble reflection and so on.On constract,underwater local dry laser-welding can obtain high quality welded joints,and becomes the current hotshot.But,there are still some problems to be settled,such as the way to obtain stable underwater chamber and the protection of back of full penetration weld.Analysis of the retrieva of underwater laser welding on Web Science,underwater laser welding technology has step out laboratory to engineering application and the in-depth theoretical research is also actively carried out on the fields of picosecond,femtosecond laser.