铝锂合金激光焊接技术研究进展

Research Progress of Laser Welding Technology of Al-Li Alloys

摘要:

先进轻质铝锂合金因其出色的断裂韧性、高比强度比刚度、稳定高低温性能、良好耐蚀性,现已成为最具竞争力的航空航天材料之一。激光焊接具有能量密度高、热影响区窄、结构变形小和焊接速度快等优势,是焊接铝锂合金薄板材料最具潜力的工艺方法。采用铝锂合金焊接结构替代机械连接,可有效提高材料利用率,减少零件使用,降低制造成本,实现结构减重。目前,铝锂合金因其自身材料特性,在激光焊接过程中仍存在一些关键技术问题亟待解决。本文综述了铝锂合金,激光焊接技术,以及铝锂合金激光焊接技术在国内外航空航天领域的研究现状,并展望了铝锂合金激光焊接技术的主要研究方向。

Abstract:

Owing to excellent fracture toughness, high specific strength and stiffness, stable high- and low-temperature performance, and good corrosion resistance, advanced lightweight aluminum-lithium (Al-Li) alloy has become one of the most competitive aerospace materials. Laser welding is the most promising process for welded Al-Li alloy thin sheet, which possesses the advantages of high energy density, narrow heat-affected zone, low deformation, and fast welding speed. For Al-Li alloy structure, welded connection instead of mechanical connection can effectively improve the utilization rate of materials, reduce the components, decrease manufacturing costs, and achieve weight loss. At present, there are still some key technical problems and issues in laser welded Al-Li alloy due to its own material properties. In this paper, the research status of Al-Li alloy, laser welding, and laser welded Al-Li alloy in aerospace field are summarized by reviewing the cryogenic progress. Furthermore, the main research trends of laser welded Al-Li alloy are prospected.