超声振动方向对激光定向能沉积Inconel 718性能影响研究  

Effect of Ultrasonic Vibration Direction on Properties of Laser Directed Energy Deposition of Inconel 718

作　　者：范伟光 李燕乐 牛家亭 戚小霞 潘忠涛 李剑峰[1,2] 李方义[1,2] FAN Weiguang;LI Yanle;NIU Jiating;QI Xiaoxia;PAN Zhongtao;LI Jianfeng;LI Fangyi(School of Mechanical Engineering,Shandong University,Jinan 250061,China;Key Laboratory of Efficient and Clean Machinery Manufacturing,Shandong University,Jinan 250061,China)

机构地区：[1]山东大学机械工程学院,济南250061 [2]山东大学高效洁净机械制造教育部重点实验室,济南250061

出　　处：《表面技术》2024年第13期44-54,共11页Surface Technology

基　　金：国家自然科学基金(52275495)。

摘　　要：目的面向激光定向能沉积表面改性及再制造发展需求,揭示超声振动方向对激光定向能沉积Inconel 718零件的影响机制,为超声辅助激光定向能沉积高质量成形提供参考。方法开展多方向超声振动辅助激光定向能沉积Inconel 718零件试验,结合原位熔池监测技术,研究沉积方向、搭接方向和扫描方向超声振动对熔池流动行为、微观结构和力学性能的影响。结果不同方向超声振动显著影响了熔池的动态流动行为,其中搭接方向超声振动使熔池润湿面积提高了86.4%,并且形状更为规则,拖尾现象得到改善。微观组织细化方面,扫描方向振动效果最佳,晶体直径细化了46.9%,水平方向的晶体等轴晶转变优于沉积方向,而在沉积方向振动下,Laves相点球化和减少最为明显。相较于对照组的显微硬度210.4HV0.2,添加沉积、搭接和扫描方向超声振动后分别提高到了232.5HV0.2、230.9HV0.2和233.9HV0.2,变化趋势与晶体直径变化趋势基本一致。水平方向超声振动影响下,特别是扫描方向的超声振动在提高材料强度的同时,还在一定程度上保持了材料的延展性;在搭接方向上,超声振动辅助显示出较好的各向异性消除能力,获得了优异的硬度、强度和塑性匹配。结论不同方向超声振动,通过不同方向的惯性力和热流改善了熔池的动态流动性,其中搭接方向超声振动在扩大熔池润湿面积和改善熔池动态形状方面具有优异的综合能力。由于超声强度方向性传播衰减和引起不同的声压梯度,微观组织细化和Laves相的细小点球状消减分别在扫描方向和沉积方向上最为显著,这些变化引起了显微硬度和拉伸性能的相关性提升。超声振动还均衡了材料的力学性能,提高了抗拉强度、屈服强度和延展性,尤其在搭接方向上,显示出较好的各向异性消除能力。可根据具体需求目标,选用相应的超声振动方向或者复合使�Inconel 718,a prominent nickel-based superalloy,finds widespread use in the aerospace industry due to its exceptional mechanical properties at elevated temperature.However,the pursuit of enhancing these properties further through LDED necessitates an understanding of the influence exerted by ultrasonic vibration on the process.To address this need,a comprehensive study was undertaken with the objective of elucidating the impact mechanism of ultrasonic vibration direction on the LDED of Inconel 718 components.The research aims to furnish a reference framework for ultrasound-assisted high-quality formation within the LDED domain.Methodologically,the study involved conducting experiments on LDED of Inconel 718 parts assisted by multidirectional ultrasonic vibration.The effects of ultrasonic vibration applied in distinct directions—namely,the building direction,overlapping direction,and scanning direction—on the molten pool's flow behavior,microstructural development,and mechanical properties were meticulously investigated.This was achieved through the synergistic integration of in-situ molten pool monitoring technology.The experimental outcomes were revealed.It was observed that the application of ultrasonic vibration in varied directions significantly perturbed the dynamic flow within the molten pool.Notably,the introduction of overlapping directional ultrasonic vibration resulted in an impressive 86.4%augmentation in the wetting area of the molten pool,which also transitioned to a more geometrically regular shape,effectively mitigating the trailing effect typically associated with the process.Furthermore,the scanning direction vibration proved to be the most efficacious in terms of microstructure refinement,achieving a notable reduction of 46.9%in crystal size.The transformation to equiaxed crystals was found to be superior in the horizontal plane compared with the building direction.Concurrently,the Laves phase particles experienced significant spheroidization and a reduction in size under the influence of bu

关 键 词：激光定向能沉积 Inconel 718合金 超声振动方向 熔池流动 微观结构 力学性能 

分 类 号：V261.8[航空宇航科学与技术—航空宇航制造工程]