面向单晶高温合金叶片的激光增材制造修复研究进展

Research Progress of Laser Additive Manufacturing Repair for Nickel-based Single Crystal Superalloy Turbine Blades

镍基单晶高温合金因其卓越的高温性能,成为航空航天发动机及燃气轮机涡轮叶片的关键材料。复杂的服役环境常导致叶片损伤,但传统修复方法难以满足其对微观组织和力学性能的严格要求。激光增材制造技术作为一种先进的修复方法,能够在较小的热影响区内实现材料的高精度修复,展现出显著的技术优势。然而,激光增材制造技术修复单晶叶片仍面临如何保持单晶完整性、控制冶金缺陷、优化狭窄工艺窗口等问题。此外,激光增材制造修复后热处理制度仍不完善,热处理后产生的再结晶等缺陷会严重影响单晶高温合金叶片的持久、蠕变等力学性能。本文综述了激光增材制造修复镍基单晶高温合金叶片的研究进展,重点探讨了修复过程中裂纹、杂晶缺陷的控制,梳理了对修复后热处理制度的探索历程并总结了激光增材制造镍基单晶高温合金力学性能的相关研究。最后对未来研究方向和发展趋势进行了展望。

Due to their outstanding high-temperature properties,nickel-based single-crystal superalloys are key materials for turbine blades in aerospace engines and gas turbines.The complex service environment often damages the blades,while tradi-tional repair methods are unable to meet the strict requirements for microstructure and mechanical properties.As an advanced repair method,laser additive manufacturing technology enables high-precision repair of materials within a small heat-affected zone,demonstrating significant technical advantages.Nevertheless,repairing single-crystal blades by laser additive manufactur-ing technology still faces challenges in terms of maintaining single-crystal integrity,controlling metallurgical defects,and opti-mizing the narrow process window.In addition,the post-repair heat treatment regime for laser additive manufacturing remains incomplete.Defects like recrystallization induced by heat treatment can severely affect the durability and creep resistance of single-crystal superalloy blades.This paper reviews the research progress on repairing nickel-based single-crystal superalloy blades by laser additive manufacturing.It focuses on the control of cracks and stray grain defects during the repair process,ex-plores the development of post-repair heat treatment regimes,and summarizes studies related to mechanical properties of nickel-based single-crystal superalloys repaired by laser additive manufacturing.Finally,the future research directions and de-velopment trends are discussed.